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A MONOGRAPEI:

BR IT I SH C O N U L A E I I Z E .

ID A L. SLATER, B.A.ri-LAT E HA RKN ESS SCEOLAR OB NEWNHAM COLLEGE, CAMBRIDGE.

L O N D O N :P R I N T E D F O R THE P A L B O N T O G - R A P H I C A I ; S O C I E T Y .

1907.

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INTRODUCTION.TTTTCilterest nttacliing to tlle systeinatic positioiz of tlie geiius Co.r~s~las. i tr,

1;ogether 36th tlie nbsence of a genernl R C C O U ~ ~f tlie British species, iiiclticecl mcto ~iac lertake he morlc fo r this mo~iogvaph,wliiclr has beeil carriecl out c1~1ringllel as t t~voycars at tlie Seclgwick Miiseiiin, Cainbriclge, md tlie British Museu~il(Natural History), Lonclon. Dwiag its Progress I have cxniniried speciincasfroin tlic Geological S w e y Collections iii Loilcloa, Eclinbiirgh, aiicl Diiblin, frolntlie Britisli Mnseum (Natural History), from tl-ie Xeclgwick Museiim, Cauibridgc,fro in Mrs. Gray's Collection of Girvan Fossils, ancl f ~ o m tlzer soiiices. I alsoworkccl a t tlie Vetenskaps-Akademi, Stoclclzolm, vlie re I mas cllablecl, by tliokinclness of Professor Holm, t o inspect n ii\im ber of Sveclish specimeiis slililcompare tliem mit11 thc British forins,

I n conclusioil I slio~ilcl ike to express mny hest tlim ks to tlie officials of t licmiiseunzs in vlzicli I liavo workecl for their iiiifailing coizrtesy nncl ltincliless, aiirlespccially to MT. H. Woocls, nt mhose snggestion I iiiidertook thc momiograpli, alidwho lias givea zne t l ~ e ost valunble lielp ailcl g~iidalice l~ron gliou t.

HISTORY.The first reference to Co7zz~lnl.in s foiind in the History of R~itliergleiiai~cl

Zlbricle,'l where the a~itlio r efers t o a curioiis fossil," the class o whicli hadnot been determimled. "The specimens nre in casts of ironstone, sometimcs foiiuclinclosed in ironstone like n iiucleus." No locality is giveii, but tlle shell is figizrecl.I n 1818 Somerby2gave a diagnosis of tlie genus Coisloiin, which M M il le , ofBristol, has very proporly institiitecl for the reception of a four-sided fossil,

1 Ure, ' History of Rutl~ergleii ncl Eilbride ' (1193), pp. 330, 331, pl. xx, fig. 7.S o v e f i ~ ,M h . Concli.,' vol. iii (1816), p. 107, l. 260, figs, 1-6. 1.

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2 TBE BRITISH CONULARIB.somewllat l-eseinbling an Ortliocera, but Rirnislied mith im pe iforate septa , aiid aiiiiiflexion of the lip that neni*ly closes tlie moiith." H e also clescribecl nnd figiiredt ~ opeCies,C. p~iadl~isiilcatend C. tarcs. Tlie former wes founded on specimeiisfrom Trallsitioll Limestone " (fig. 4), "Bris tol Lirnestoiie nboiit tlic Hotmclls "(fig. 5), " Traiisition Lirnestoiie th at contailis inica fr om iiear I Icsa ic lc" (fig. 3),alid (( Tronlie Raiik near Glasgow " (fig. B), nnd js IIOW knowi~o iiicliide tlireedifferent species, mliile the lntter was dou1)ted at Llie first by its autlior, nnd mnssoon after-ivwds recoguiscd to be an O~*tlioccs.as.In 1828 me find the species C. soiuei~h!/i st tr ibutecl by da Rlaii~ville~o Defi-nnce,with n refereiice t o tlie 'Dictioi~nai~elcs Scieiices Nat~irelles.' De Blnix-ivilleyepi*odiicecl 11 Somerby's six figures, and g w c no clescriptioii; as all nttemlits tofiiicl aily acco~int f C. so~,ue~.llyin tlie ' Dictioilnairc ' hnve proved irrisuccessfiil,Defra~ice's iglito the species seeins to be very cloiibtfnl.In 1839 Soworby2 clescribecl aiicl figiired a IVoiiloclc T~ii ne st oi ~eorm miclcr tlieoriginal iime, C. qzral-k~ismlcata, neiitioiiii7g, liomover, that it iniglit bc foiiilcl.possible to sepaiqate liis froin the Carboili-ferous Limestoile species, j i ~ vliicli cnseDefmuce's name sliould be adopted for tlie forinor. Tlic iiex t iiew species wasfouncl iil Irelancl, co. Tyroile, ailcl mas clescribecl ailcl figured by Portloclr u~iclcrt l ~ e laine C. elongata, togetlier with two otliey sl~ecies a,rned respectively " G,qz~ad~iszilcatn,OTT.var. C C I T ~ . " nc1 " 01. qzind~islilcntn, Sow. var . sil." Tlie twofigiired specimeiis of thelat te r beloiig to two d istinct species. The ae xt importalitreference to the geiius is in the 'Geologie cle l n Riissie d 'E~irope,"~vIieredeVeTile~iil,n tlie Palzeoiitological Section, defiilitely restrictccl Somerby's .iiaine, C.qzind~iszilentn, o tlie Cmboiiiferons species mcl aclopted D ef ra xi c~ '~ ixe, C.sozuerliyi, for tlie Silurian species, distingiiished by its greater sizc, comyressedform aild contli~nuour,zisverse folds. The d e s ~ ~ i p t i o ns accoinpniiied by a clearfigiire, aiid sinoe tllis is the first time tl iat tlie two forms nre c1efini.tel.y sepnra tedmd na~ned,lie species C. so~ue~liyihoiilcl. be assigned to dt! Venie~ii l .

111 1847 Sandberger ' p~ihlished n11 im portau t monogrnph 011 PnlsozoicPteropods, in vl~ichhe describetl aiid figiired fouyteen species, incliidi~ig liiongthem tlie three known Britisli foms, biit givii~go tlieni new and more clescripti~~eliames, whicb, however, h a ~ eot boen ~c lopted . He also pve a geiicrnl closcriptionof the geniis, md % ]ist 0.f those characters iipon ~~hi.liichie based liis specificdistiuctions. In 1855 MrCoyG tteinpted to cleax up tlie confusion in nornencla-

De BlainviUe, 'Mdacol.' (1838), p. 377, pl. xiv, figs. 2 C-s.Sowerby in Mu1'cliison, ' Silur. Syst.' (1839). p. 627, pl. xii, fig. 22.Fortlock, ' ~ e p o r t , eol. Lonclaodeily ' (1843). p. 393, pl. xxix a.De Verneuil in M ~ ~ r c l ~ i i o n ,e Vei.11e1ul arid dde I(eyserling, G fol . do 11nRusus d ' luropc ' (1845)'vol. ii, "Piildont.," p. 348, pl. xxiv, fig. .

"F . sandberger, "Pte~opocla er ersten Erdbildungs-Epoche : Oonulmit~ nd Colooprioii," 'NeuesJ I L ~ ~ .u1' M&., etc.,' 1847, p. 8.6 F, M'Coy iii Sedgwiclc's ' Spops . Br it, P& l~ oz .Looks (1855), pp . 287, 520,

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HISTORY. 3ture by substitiitiiig Sanclberger's name, C. cartcellatrr, for tlie 0. sozue~~Oyifdoub tful origin, anci by restrictiiig C. qz~ecl~isalcntil.o tlie Carboniferoris species, asIiad already been doiie by de Verneiiil. I n tlie Al~pend ix ' to the same workSalter described aucl figured a uew Upper Siliirian species, C. subtilis, wLich isalso refeilrecl to by M'Coy in t he te xt. 1111866 Salter ' cscribecl and figured foiirspecies, C. lzvigatn., C. l~omf~a,yl;,. a~wgn~-iti$Ljl:.n,licl G. coy~ium. In 18G7 tlie~ il o st mportaiit work npoiz this geiius appewecl in Barrande's 'M on ogr q~ hofPala.?ozoic Pteropocls,' in wliicli lie describecl anrl figurcd tweiity-seveii Boliemianspecies, giving also a geiieral acconnt of th e geiius, details of structnre, ai~cl liehor izontal mlcl vertica l clistributiou. I n 1873 Stllter ,h catalogiiccl, withoiit descrip-tion. or figui-es, two iiew species i n tlie Wooclmarclian Afuscuni, Cambriclge, ~ n id e rthe aames C. clnvus ailcl 0. O$~~8scintil..The former, beloilging to tlie FletcherCollection (reg. no. a. 878) is saicl to colne from tlie Weiilock Liinestowie nearDiidley, and was ciescribecl ancl figarecl by Cowper Rcec15 in 1902. As, bomever,bot11 iil climacter alilcl pyeservatioii, tlie fossil is icleiitical with small specimeiis ofC. p~ind~~isz~lcc~tc~roin tlie iroiistoiie nocltiles of tlle Goal Measiires, aiiicl is totallyiinlike any fossil I have Seen frort1 tlze Weillock Limestoiie, I a;xn o opil~ion 'hnta mroilg horizoli has lecl to tlie instit~ition f a false species, wliich must tliereforebe abaizdoneci, With reg~arclo C. bifnscicctc~, lso describecl alid figured by CompeiReec1,Qhe species mas uwrecognisable froin Sa lter's iiote, aacl tlie Same form inSweden was described ancl figured eleven years later by Lindstrm," unclerthe ilanle C. asyersa,; Lindstrm's ilaine, mlcl not Salter's , shoiilcl therefore beaclopted for t lie species. Bnothor nem species was aclclecl t o tlze list iii 1875 byH i ~ k s , ~lio describecl and figilrecl a somewhat cloubtful form froin tlie LowerOrclovician of So~ithWales uncler tlie name C. l l n ~ ~ u i ~ . ~ ~ e ~ ~ s i s ,liree years laterwe find a reference by Etlieridge t o some fragmeiits of a nem species fYoni t'heLower Caibowiiferoiis of Scotland, a~ l dlzese fragmeiits ~mcloubteclly eloag t o thenew species, C. tenz~is,described stibsecluently. I n 1884, in the importailt woiio-g r q l i to whicli reforeilce has alroady been marle, Linclsti.oni clesci.ihecl mcl fig~ireclfive spscies from Gotlmd, slncl iil 1893 R o l m ~ o o i n ~ ~ l e t e dhe clescription of tlieSwedish .members of t he fainily. I n aclditiou to tlie clescriptioil o riiiie iiew

1 Loc. cit., Appendix 8 , 1. vi, an dp . 287, pl. 1.L, fig. 24.2 J. W. Saltei, in Ramsny's ' Geol. Noith Wales,' Mem. Geol. Siu.v., vol. iii, ecl. 1 (1866), pp. 354,355; ed. 2 (1881), pp. 562, 563, pls. X, xia.8 J. Barrnnde, ' Syst. Silur. du Ceiitre cle la Boheme' (18G7), vol, iii..& J.W. alter, ' Catnl, Cambr, ancl Silur. Foss. Geol. Mus. Cnmbr.' (1873)) pp. 153,171.5 F. R. C. Reed, ' Beol. Mag.' [4], vol. ix (1902), p. 123.6 G. Linclstroui, " Silur. Gastr. ancl Pterop. Gotli~ucl,"E. Svensla Vet.-Akad. HmcU.,'vol, xix,

no. 6 1884), pp. 3 9 4 7 , pls. i, vii, xix.7 H, Hicks, ' gUart. Journ . Geol. Boo.,' vol, xsxi (1875), p. 189, pl. xi,figs. 5, 6.8 R. Etheridge, jun., 'Quart. J'oura. G801. SOC.,'VO~.xxiv (1878), p. 19.9 G. Holm, "Hyolit1iida ocli Coniilariicla," ' Sver. Geol. Undersok.' (1893), ser. C, no. 112.

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GENERAL MORPHOLOGY. 5(i) Tbe sicles nie straight or sliglitly concave tlirougliout tlie leizgth of

the sholl, e. g. 0. lzziigatn.(ii) The s tra ight lines alle replacecl towards the apcx by coilvou curves,

while tlie shorter ax is becoines still morc diiizinislierl, giving riseto a flatteiied ellipse or figure a, . g . C . .sozoe~.OyY, C. uesiczilccris(1'1. V , ig. 4 [ I ) ,

(iii) The sti~aiglitiiies are replacecl by convex curves throughout, giviiigrise to aii ellipse, e. Y. C. co7nl11u~zatn PI. IV, fig, 13).

In one soinewhat do ~~ bt fi i lase the sidus a~pear o be eqiial iin pairs, giviilgrise to a rectanglc, G.'!/. G. y i i ~ ~ c t e t aPl. I, fig. 1 0 1,)).

(3) Pctces qf Ihc Pylvm'~i~l.--Exceptii the cloiibtfiil cascs of CI. la't.igottr. aliclC. p z ~ 7 z c t ~ l t n iliong Britis ls species, the faces of tlie pyrairiids are eqiial, auc1siinilar eloongatecl. trislilgles, with siirfaces eitl~er lane or vitli tlie inoclificzltioils~nentionec l bove. The apical angle of tlie face can freqrieiltly bc inensurecl, even~vlieii he specimeil is very iiiiperfect. I t is nsnally foiiiicl t o have a, fairly coiistnntvaliie for a species, ancl is therefore of consiclerable specific importance, It is notreaclily affectecl by compression of the sliell, as is tlie case with ilie apical angle ofth e pymmid, llience the v a l ~ ~ e siven are genercllly reliable. Wheu the shell teucls.to become prismatic towarcls tlle q e r t u r e , tlie angle of t he facu becomes corre -spoiidingly less.

( 4 ) L o n g i t t ~ d i ~ z a l ~ o o z , es cmr7 R.iclges.-The faces are separatecl from oneaiiother in all casss by straiglit,'well-marked, lougitiidinal grooves, wliich ruiidown the aiigles of tlie pyrainid. Tliese marginal grooves " vary greatly incha racte r, but clre very constaizt for a species. I n d l tlie earliest forms the y a resmooth, cleep, ancl witli n tenclency foy the edges t o become prominent, as inG. co l so l zn tn (Pl. 111, fig. 1 n) and C . lr.o7nfi.~@. I n t l ~ eater oriia~nented ypesthe orriamentation of th e faces rnay be continned across the grooves withont cliangein clirection, as in C. suri;eltbyi (PI. V , ig. 10 ir) ; or it may charige its clirection attlie edges, and oease at th e basc, as in G. p ~ i a l . i a d c a t a(PI. 111,fig. 2) ; or it maycease abruptly at tlie eclge, leaving a smooth groove, as in C. b r e v i c o ? ~ o ~ t nPI. V ,fig. 13).

I n sliape also there sr e all stages, from a sharp, mell-definecl groove, such asis Seen in C. l ~ i s p i d n Pl. 111,fig. 9 n ) ; o th e wide, sliallow iindulation seen inC. c r a s s n (Pl. IV, fig. 4 a).

On he surface of th e face itself longit~iciinal rooves a re sometimes seeri. Inthe eailier srnootli forms tliese " acial grooves ) ' are constant, ~ e l l arked, aridfreqiiently resemble tlie marginal grooves in having prominent, raised edges (e. Y.G'. c a ~ o q z a t a ,PI. 111,fig, 1 a) ; bilt in most of th e later species, if preseut a t all,the y appear a s narr ow clel~ressions, r frequently an fine cracks, markiug tbe line O Eweaixnese, along which the trarisverse ridges are beilt. They are always ceiitral or

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6 THE BRITISH C ONULAR IB .sirb-cciitral, accorcling to tlie position of tliis bend. In C. nticqdoscopicn (PI. 11,figs. G, 7), they are ~rnrisirallydeep aiid constaiit. Secoiiclary fac ial grooves,dividing again tlie lialf faces, are oiily seen iii tlie early smooth forins.

I n tliree specics th e centres of tlie faces are marked by fine, internal,longitirdinal ridges, tlle internal septa of Liuclstrom.' I n Brilis li form s tliey arein pairs in C. pz~izctntci.(Pl. I, figs. 10 a, 11) and C. aspersa (Pl. I , figs. 5, G b ) ,aild single in C. telrzhis (Pl. 11, fig. 2). They slpl3eai. to be fine, biconvex ridgeson the inner siirface of th e shell. As tlie resirlt of compressiou, a ~ i d ~virig o th ethiniiess of the shell, iii the two lattey species they me ofteii seeii as rai sed iid ge son the outer surface ; in C. n.spe19sn liese yiclges are ~isii ally ccoiupa1iiec2 by ablack staiii, probably iiidicatiiig tlie positioii of soiile im po rtan t ailatomicalstriictnre (Pl, I , figs. G B, 9 C).

(5) ilper*tlclt~ r.nd A11se n Xhe1l.-Tlie aperti rre of th e shell is not cominoiilypreseived, though iriaily perfect examples are knowil, espocially alnoilg specimensfro in irolistone coiicretioils, Each face terminates in a roiiglzly trian gu lar lobe,on wliicli tlzc geiieral ornamentatioii of the face is contiiiuecl. Geilerally theselobes a re shoyt and rigicl ancl bellt down a t rig lit angles t o bhe axis of th e ahell,partially closiilg the aperture, as iii C. q~inli)l~isz~lcatnncl C . sozirel-byi (Pl. 111,fig. 6; P1. V, fig. 8) ; but in C, aspersn they are loiig, aiicl meet, forming m elevated/ cone (PI. I, fig. 5 ) ; in tLis species bhe shell is very tliin, and the apertirral lohes

" were probably iiot rigid,I n th e grea ter niliuber of speciulens th e delicate apical portion of th e sliell is

iiot preservecl, biit examples are foirncl in some species where tlle pyrailiicl t a p r sto a fine point. I t is generally difficirlt to make oirt whetlier this encl was closeclor op in ; bnt in one species theTe seeins goocl eviclence th at the la tte r sta teprevailecl. C, tenz~is s fouild in a good state of preservation iii the liard, slialyCnlciferous Sanclstone of Gleilcartliolm, Dumfriesshire, aiicl 011 shbs o tliis rockexamples are founcl iil clrrsters, varyiiig iii n i ~ i l i b e ~rom two to as many as sixtecri(Pl. 11,fig. 1). Tlie size of tbe indiviclnals of th e cluster varios, soine be iiig quitesmall ancl some f d 1 gromn. They iiiirst have been connected with one another or withsome foreign body by their apices, which miist tlierefore have been pierced d u ~ i i igsome par t of the life of the animal, I have fouiid no trac e of this fixed conditionin any other species, nor hilve I focrud any reference to it in pirblished works,except in a sliort article by R ~ e d e r n a n n , ~ntitled " Note on a Bessile Co ni~la iian."H e clescribes this fo rm as a typical Coilularian, in whioh the delicate pyramid baseis inseited in a, ahitii io~~sup, which by meaiis of suction acted as a temporaryo rg m of attaclime11t. The attaclimeilt in th e ca,se of C. t e ~ ~ u i san hardly have beeiltemporary, arid from the size of the individuals mu st have been an aclult characte r.

I n s h r g e nirmber of species, instead of tape rin g to a. fine point tlie pyramid isG. LinCLstrom, 'Sil~v. ostrop. Botland,' P. 46.

wA uerican Geologist,' vol. xvii (1896), p. 158.

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GENERAL MORPHOLOGY, MEoancl ending in a more or less convex septiiin, ~v liichSowerby iioticed as loilg agaas 18 39 (loc. c i f . ) , aiid vliich pve risc to tlic iden tlla t tlie geiiiis shoulcl bc placedin tlie Ceplzalopocls (Pl. V, figs, 12 ( L , 14 U ) . Tlie septnln consists of a -rclXythi ii sliell, whicli alspears to be continrious ~vi tl ihe iniier layer of tlie test . It isqtlite unorziainentecl, tlie stria3 ~vhiclia c ofteii seeiz lnarallel vith tlie longcr nxisbeing probably dne to coinpressioii (PI. V. fig. 7 b). The position at vahicli it isfoun d varies coiisidernlnly, for i t is sornetiriies close t o tlie apex, n~ he re t onlyincasiires about 10 inin, across, vhile in 0 t h cases, iii specinieiis of abont the Samesize, it lies a leilgtli. of 25 inin. or more. Probnbly, tlierefore, tlie alnical par t oftlie sliell is clivided up by a series of septa, of mliich only tLe lo~vcst s iisi~a llyseeii. 111 the Biriniagl~ainUiiiversity Museiiii?, liowerer, tlierc is a specimeiimhicli shon~s a secortd septum archiiig avay abont Ci mm. bore the first,Tlie existeiice of a siphuiicle iii tliese septa ]las been suggested a t rnrioustim es by differeilt mrite rs,l but iiever mith aiiy grea t ccrtainty. Tlie septnare freqiiciit1,y ii~iiclibrolren, lnut I liave seeii sevcrnl perfect olles. 011 onlyorte of thcse (PI. V, fig. 1b ) linve I observed aiiytliiilg like a sipliiiiicle, aiiciEiere, tlzongli tlie sind1 central tube is very mell defiiicd, it appears to be closed,ancl nlay be aii nbortivo siirvival of a once fuilctioilal sti-uctiire, or a scar leftby the gromth of the septnm.

I n d 1 probability the chainbers tlius snccessirely ciit off a t the al>ex remaiiieclcplite empty, a~idlie apical oaas mny eveii linve been lost in thc lifetimc of tliealiimczl; af ter th is h ad taken place the apical eiicl of tlie shcll must hm e beeiiclosecl. R ut in soine species, where tlle sliell is exceptioiially thin, scpta nlnpcar tobe iii~kiiomn.Possibly in all these cases-certaiilly iii C. tn~zcis-tlic slrell reinniaeclOpen at the apex, ailcl was fixecl to some foreign bocly.

( G ) 0rie~ztatioiz.-Iii total ignorante of tlie nat.ure of tlie soft pwts o tlicanimal, aiiy distinctiou betweaiz clorsal ancl ventra l sides i n ~ ~ s te iyicrely anarbitrary oiie. Saltey writes, in 1855': " If v e consicler, as it seerns to me weou gh t to clo, tliat iii tlzis compressed species the two opposite ailgles of tlie fiatter

' sides a re tlze dorsa l a ~ i d eiit ial oizes, Jve sliall theii, I thiiilr, liave a character bymhich me iuay be able t o trace tliese pwts ii z t l ~ e quarer species and in soinewhich a r s probably compressed laterallg. Po r I fiiicl. tliat the line vhere tlie nsnaltraiisverse rib s aye beizt or broken a t about the iniclclle of each lobe is izot really ii zt,lie middle in a ll cases, biit is nearer th e dorsal aiicl ventral aizgles tl im tlze la teralones ; ancl again, th e tmo lobes mhicli form tlie clorsal sicle are somctiines widert l i a i~hose tw o wliich forin tlie veiitral face,"

Biit tliis czttempt a t orieiitatioli seeins to ine to be of little valiie. Tliesqliarer species " are, ia all cases ~vh iclr hare observecl, syrnmct.rica1, aucl as tlie

1 Rueclemaiui, ' Amerioan Geologist,' vol. xviii (1896), p. 65 ; Sowerhy, l oc , cit. (1839) ; Hau,Pddeoiit. Nem York,' vol. i (1847), 11. 222, pl. lix, fig. 4!e.

2 Sedpick , ' Synopsis of 13rit,Paleooz. Rocks,' Appendix A, p. V.

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8 THE B R ITISH C ONULAR IB .positioii O E tlie sliell in lifc was lirobably iiy~riglit, t is ~liffic iilt,witlioiit tlie softparts, to distiiigiiisli doiwd aiid veiitrnl sides. In descriliiug t he compressed formsI ~ I R V C sed tlle terills ~ e i i t r n l ~ ~iid " ateral " marginal grooves for the snlce ofcoiiveilie~ice or expressiiig, rcspectirely, tliosc a t th c ex tremities of tlic sliort anclloi1g cliaineters of the cross-section.

(7) O I ~ ~ I I L ~ V / ~ ~ , ~ , ~ ~ O ~ L , - Ainall nuiilber of tlle earlier ineinbers of the geiiiis h w esmootli shells, biit tlie majority sliom a ve ry delicate niiil beautifii l ori~ ~m eii tati on ,cliffering grea tly in dif fereut species, dtho iig li iisunlly coiistaiit for eacli species.Auiong Britisli f o r m tllis ~ri-iainent~atioiis e~seutinllya trcziisverse olle, thongliiu soine f o~ ei gu pecies a, longit~id ina l lircctioii prcvails ( P . ;I. C. scolrri2s, Holm).

Eacli fnce is typically ccrossed by n series of iidges, sepnrated by f ~ i r ~ o ~ ~ s ,iidbent iip regiilarly aloiig a central or siibceiitral liile, so :a to forin lz successioii ofclievi-011s oycniiig tomards tlie aliex. TLe angle of tlie clievron varies froi~i180'to little ovcr 90". Very nsnnllg the aiigle i ~ i c ~ e ~ s e sii siae f ro m tlie npex tom ards tllea ~ w t u r e , iit in aiiy olle spccies is fairly constalit for tlie contral pstrt of tlie sliell.Tlio straight sicles of tlie clievroii iiiay be rel)lacecl by siliiyle or com pound curv es, Tliet.1~0icles of tlie clicvioii are syinliiet'rical iii tliose ~p ec ie s iavilig a sq i~ a re ross-sectioii (Pl. III, fig. '3 a), b ~ i tmliere a, coiiiliressecl foriii is tlie iintnral onc tlierirlges very frequeiitly fall smay lnore sliarply t o tlie latcral tliaii t o tlie ceiitralmaigiiial grooves. JTitli tliis cliaracteia is ofteil fouiicl a sliiftiiig o i the poiiits oftlie clievrons tom ar~ ls lie ceiitral inargiunl groove (P l. V, figs. 1 L , 7 ( 1 , ) . Thcsefea turos ofteii afforcl ,z clue to tlie ilatiirsiil cross-sectiou, vlioi~hc latter caniiot beclirectly observecl. Tlie riciges vary iii wiclth froiil coarse bass, iiearly 1min, wide,as Seen in C. CI'CLYSCI (PI. IV, fig. &(L), to tlic filicst strize, invisible except ~incleitlie microscope, RS iii C. ~ ) ~ . ~ C Y O S C O I J ~ C C IPl. 11, fit;'. 9). 111 5111 indivicllial ex ai~ ipletb e ridges iisiially bccoine fiiier a n ~ lnoie c r o ~ ~ c l e ~ lt tlie apex, aiicl ofteii czgniii t~ ttlze ape rt~w e, ut for the cea tie of tlic shell a fai rly coiistaiit spaciilg is inaiiit-cziiiedin any olle species.

Tlie cletails of o~namelitatioiivary eiiormonsly. Tlie ridgcs we sometimesqnite smootl~, iit more frequently the snlnm its are stiidclecl ~v it ll iiie tiibercles,ronacl, or less commoilly eloiigated, trim gi ila r, etc. Tlie tiibercles inay be pro-loiiged as fiue poiiits 011 to th e i ~ t e ~ v e n i n gurrom, as iii C. I~ i s y i~hPl. 111,figs, 9 b,11); o i may be confinecl to the riclges, as in C. giobosn (PI. 111, fig. 7 n ) . I na consiclerable ilumber .of species a vell-marked loiigituclii~al t~ia tio iis seon in tliefnrrows between the ridges; tliis is nsually finer tl im th e nmiii transverse riclgirig(Pl. V, figs. 2 a, 1 2 b ).

I n a fern cases the tr ansv ~rs e idges aile represented b y roms of ti~ber cle s,arrangecl regularly across tlie shell, as in C. asyemch and C . p z~~ i c t a t c ~Pl. I, figs. 7,

) Strwchure of tha Skel1.-The shell in tlie Brit isb species is a lv ays ve ry thin ,md often very inuch less. It appears to

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ZOOLOGICAL AFFINITIES. C1liave covsistecl esseutially of some cliitiiiaiis material, iimpreg~iated owctiincs witlia certwiii ainouat of lime. lii tlie greatler iiiimlser of species tlie sliell is iiinrlc upof tmo ~li st in ct wyers; tlie outer is nsiially clark-coloiired, semi-t,raiisparciit, aildliighly ornameilteiS; thc iniier is of a 13a1eT colonr, morc opaqiie, tliiiiiier, niid iiearlysmootli (Plate V, fig. 10 1 ) ) . 111such trailsversc sectioils as I have bceu able toobtaiii th is divisioli is n ot well mnrkcd, biit tlie tv70 layers are ofteil clearly secn~vherohc oiitcr is pnrtially flnkecl off. 111ome species wliere tlie shell is cscep-tionally thiii it is appnreiltly cjiiitc l~omogeiieoiis. Tlic strizct~ii~ef tlie sliell isbest seon iii some speciincns of C. ii,irrrliisiilcr;t,i froui tlie iroilstoiie nodiiles of th eGoal Measures.

( 9 ) Pl.cse~~/oc~tionf tllc ,Sllell.-Tlie sliclls ar e preservecl ili liinestoiies, sanrl-stoiies, shalcs, slates, mcl iroiistoiie nodulex. They are alvays l i d ~ l eo coiiip~esxioil,tlie resiilt boing iii some cases actiial co~itact et~veenlie iipper ancl iiiider faces. IWlieil tlie specimcils nre lsirge tlicy ailc selcloin perfect, the npertiiral l ~str t eiiigIsrokeil amay inore ofteu eveiz tlian the apical portioil. Frcqueiitly also only olleor tvo faces are preserved. Soinetiines tlie differeiit layers of tlle sliell are seeniii an excellent sta te of preservation, especially in speciinons froin tlie iroiistoiiei~oclnles;bnt inore ofteii the oiiter lnyer is coiisiclcrably clarnagecl, an d aloiig' thesnminits of t he riclges tlie shell mey be eiitirely garte, little isolated 11o~tionsrernniuing in thc furroms (Pl. 111, fig. 4 h ) . Lastly, iii a lasg; niiinber of oases110 shell is preservecl, aiid the fossil is iii th e fo rin of either an exteri1al or an

DISTRIBUTION OP THE GENUS.Conzrlcwia, tliough never really common, is fouud distribiitecl throiigh tlie

Rritisl-i rocks froin th e U ppe r Cambriinn t o the Upper Cmboniferons. Dnringtliis period th e maximnm development was renchcd iii iYIiclc1le and Upper Ordo-vician aiid Siluriall tiincs, vh ei i t~veiity-tnro out of the thi rty British speciesocciirrecl. Above tliis horisoii tlie niimbcr of species rliiiiiislies, fivc appear ing intlie Carboniferoiis rocks, only one of mliicli snrvivos ia Upper Carboniferons tiines.Examples are foiiiid in tbe Bidleigli Saltcrton Pebble Bcd, I~iit hese we al1clerivecl. [See Table on p. 10.1

ZOOLOGICAL AFFINITIES.Tl10 position i11 tlie aiiiinal Iringdo~n ii whicli tlie geiiils Cunalc~~rinhoulcl be

placed, Las been a siibject of contentioii froirt tlie time wheu S o ~ e ~ b yrote, iil1821, tliat

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ZOOLOGICAL AFFINITIES. 11surprise that a theory, not possessilig even the appearance of pr~ba~bility,lioulclh a ~ e eeil accepted as a fact witlioiit m y E n d of pi*ooE. B e considercd thedeteiminatioiz of the systeliiatic position of Co~ z u l i ~ r i no be ri, matter of greatdifficiilty, bnt snggestecl that it is most probably allied to the PalsozoicCapulidz.

In 1881 von Ih er in g placecl Corz~~iarin ith tlie other so-callecl PalzeozoicPteropocls iii the class witli wliicli it was first associatecl. Ele consiclcrecl tliattliese simple chainbered fibells coiistitnte tlie earliest aild iliost pri-mitivc gronl:, ofCeyhalopods, alliecl to th e Orth ocera tic l~, rid. i~ameclby hiin, oii accoillit of t'lietliiiiness of tlie sliell, " Leptoceratiteii." Froiii this grou~i , accorcling to vonIhering, arise ou. tlie olle side the Tetrabranchs ,zs cz small offslioot, aiicl on theoth er t he Dibranchs (iii wliicli ho incl~rdecllie Ammoiiitcs) as tlie rnairi branch.

Linclstrm," iil 1884, criticisecl tliese conclnsioiis. He statecl that in his opiiiiontlze exte rnal siniilarity of soiue species of C1io (or Cliodo~rz)o a Con~~lariarihellwas ii ~o st trilriilg ; tliat the intern81 loilgitnclinal septa fou~icl n a few spacies(G. g. C. nspei-sn) were laomologons to similar striictures fouizcl in OZio, S1'plialcc.,etc ;tliat tlie typical oriiaiiieiitation o l a Coniilariaal was al~proacliecl n some species ofClio ; anti fially, tliat among living Pteropocls fornis iliffered safficiently widelyto mako aily clisc~~ssiou f close corres~~onclencennecessary. He thereforeretaiilecl the genns mit11 the Pteropods.

In 1889 Pelseneer endeavoirrecl to prove t l ~ a t he " P r d t e ~ ~ ~ l ~ i stBiopoclesPrimaiyes" hacl ao coniiectioil witll tlie inoderai Pteropocls. He based liisconclusioiis on : (1) Tlie form ancl clini*acter of tlie Comlariaii shell, a11d (2) Jieprobable orig in of t he Pteropocls. Altliongh liis argumeilts were nnswered, eachiii t ~ i r ~ ,y C. WiinanZhn 1894, it appears t o me that liis ileductions ns to theaffinities of modern Pteropocls cm no t be r e f ~ t e d . ~

After prolougecl stncly Pelseneer has come t o th e coilclusion tliat tlie Pteropodsare not a primitive, biit a liighly specialised group, clerivecl Eroni two cliffcreiitsoiirces : (I) th e Thecosomatons Pteropocls (with which Co~zzil(o~in ns associatecl)from Biilloiclea-like Opisthobraiiclis, ancl (2) tlie Gyiiliiosoruatous Pteropods fromAl~lysioiclea-likeOpisthobranclis.

Th e evideiice for tlie highly specialised natiiio of tlle Pteropocls is scen in theirinarked asymmetry, ancl th e g re at concentr,ztioil of their iielavoiis systerii ; aiid iutheir embryology. As the embilyo is even inore ~ s y m e t r i c a lhan the ad~ rlt ,lieym s t be derivecl from ancestors alrendy higlily specialised, aild the appai*mutsym metry is acquirecl by' adaptation to natatory habits.

1 H. von Iliering, 'Neucs Jahrb. fiir Min., etc.' (1881), vol. i, p. 87. ,2 G. Liilclstrm, 'Silur. Gtastrop. niid Pte rop. of Gotlancl ' (1884), pp. 39, 40.3 P, Pelseiieer, 'BuU. Soc. Belge cle Gdol., etc.,' vol. iii (1889), Mem., pp. 126-136.4 C. Wimau, 'Btill. Geol. Inst. Upsdu,' vol. ii (1895), 11p. 114-116.5 See dtlso Pelseneei., 'Rep. Challenger Expedition,' vol, xxiii, pt . i (hn to iny) , p p 15-96.

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12 THE BRITISH CONUIJARIA.Pelseneer, therefore, 11as given iip entirely th e iise of tlie term " Pteropoda " '

in zoological iiomenclatiire, and lias iiicliicled tho tbree families of "ThecosomatousPteropods," witli B iiiiinber of otlier Gastropod faiiiilies, in liis Tlaibo BullomorphaJSlc6-aviicr Tectibrnilchiata, Oo-d(

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TllE BRITISH CONULARIB.

SYSTEMATIC ACCOUNT OF BRITTSH SPECIES.

G e w s CONULARIA, Sowerby 1818 [ex Miller MB.]Dinysosis.-Sliell a four-sided, elongatecl pyrauiid-ncwly alwa~ rs straig lit.

Cross-sectlioa a scluare, rholnb, rectaizglo or rlioniboiil, or tlie correspoiidirigfigures wliere tlie straigh t lines alle replacecl by c i ~ ~ v e s . aces of tlic pyramid flat,couvex o r concave; all eqnal or eqiial only in opposite pairs . Angles of thep y r m i d innyBedby straigl~t roovew. A p e r t ~ ~ r eartially closed by infolcling lobes,apex shaTply tapering; apicel pailt of shell clivicleii up into a few compartnients bythin convex, probably imperforate septa. Shell smooth, or oriiam ented wi th ase ~ ies f ridges, soinetimes longituclinal, niore ofteli ti~arisverse. Shell ve ry thiil,formed o cliitin, more or less impregriatecl with lime. I

Shell withont traiisverse ornm entation, except g~ o ~ ~ tl i -l i n e s .(A ) Sllcll large, very thin ; ma~ginalmcl facial grooves well rn:~~lic d growth -

liiles irregular and of teil iml~erceptible.(i) Shell smooth, except for a single ridge dowli th e cen tre of tlie face .

C. ZZnlzvil*lze~zsis,'iicks.(ii) Sliell with a well-marked central Eacial groove, flankecl by two very

faint secon day grooves ; tapering of shell very gradual.C. c o ~ i t ~ m ,alter .(iii) Marginal anii ceiitral fncitll groovcs boiuided by prominent odges ;

tapering of shell more rapicl. C. honfinyi , Salter.(B) Shell small ; growth-lines strongly marked.(i) Marginal and central facid grooves stroiigly niarked alld usually ~vitli

promiizant edgos. Growtli-lines horizontal. C. Z ~ ? Z ~ ~ C L T S S O ~ ~ ,Iolm.(ii) Facial grooves absent; growth-lines gen tly arclieil across tlie face.

C, avigat~b,Salter.Conularia llanvirnensis, Hiclis.1815. Convlaria ll~nvir~ensis,. Hicks, Quart. Joimi. Geol, Soc., vol, xxxi, p. 189, pl. xi, figs. 5 , 6.

Diagnosis.-Shell large, very thin , tapering uniforinly ; cross-section unknown.Faoes flat, apical angle of face 5"-6'. Marginal -groovounknown ; stroiig c?iitral

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I

C ONULARIA CORIUM.ridge ( T ) . Apertnre u nkno.r~il;apex pointecl ; apicnl scpta unlrnomn. Oriininei-ita-tion abseilt; lincs of gro~vtliiidistinct.

Dime7~sio1zs.-Length 150-180 min. Wiclth of face 30 min.D~-sc~~Q~tio~z.-Thisliell is fociild iii a bad statc of preservation iii tlie Upper

Aieil ig ancl Lomoil Llandeilo roclcs of Soiitli Walcs. I t seeins to be of ii somcmhntdoiibtfiil n a t ~ ~ r e . lie "s troiig central riclge," mcntioiied by Hicks, is onlyoccasionally seen, ancl tlien appears to be ~ ner el y liiie of wealrness, along wliiclith c shell has yieldecl. T l i e ~ e eein, iildeed, to be fern cliaracters iii proof of itsgoiieric liositioil, ancl those foatiires by ~vliicli t is distingnislied froin C. c o i s i z ~ i nareof ,z iiegative kincl. Ho veve r, ~i ii ti l etter sl~eciilzclis re obtaii~ecl, hich lnay liioveo r clisprove its riglit to specific distiiictioii, I hare retaiiied C. lla~zvimc~zsiss aseparate species.

IIoil . iar)~~~ ~ r locctiiLy,-Uplier Areiiig : Idanvim .T!lpe.-Scdgviclr Mnseuin, Cambridgc (reg. 110s. 19, 20).

Conularia corium, Salter.1866. Conularia col?tmt, J . W .Salter, iii Rainsay's Geol, N. Wales, Mein. (X-eol,Surv., vol. iii, ccl, 1,

p. 355, pl. xi A, fig. 11 (also ed . 2, 1881, p. 563).Diag~zosis.-Shell large, very tliin, tape ring nniforrnly; cross-sectioil n n k i l o ~ n .

Faces eqnd, slightly conwx apically, concave apertarally; apical ai~glo4'-5'.Mw giiia l groovcs narro-cv aiicl stra ight, teiiding to becornc prominent tomarcls th eaperture. Centra l fac ial grooves ~ ~ ~ e l lnarked; sec~ncla~yrooves 011 either sidefaii lt, convergiiig slowly. Aperture, apex, and apical septn iiilknoma. Ornarnelitn-tioli abseilt.

Dimarzsio?zs,-Length aboiit 250 mm. (?) Width of face over 30 miu.D e s c ~ i i o - T species was described by Salter in 1866, and still a t tlie

~ r e s e n t ime very fern examples are knomn, Hence little can be adclecl to llisclescription. No specimen that I h w e seen, is iiearly pcrfeot, aiid all a re badlypreseived. Th e seconds~ry acial grooves, about 7 mm, a p a ~ t t the apei~ti iralend,slowly approach one anotber to~vardshe apex. They are very faint dong theirwliole corirse, arid die away before rcaching the apex.

A,fivzities.-Salter compared this species with C. py~~a~ni i l idaf tbe l\llay Sancl-stone (Ordoviciail), b.ut it differs from this in haviiig the faccs cqiid, cz snlczllernpical angle, and a sinooth shell. Of Br itish species, it is r~ndo~ib tecllyloselyallied t o 0. l l omf~ay i , rom which it is distiiiguishecl by the slow rate of tap er ingan d the simple nature of the marginal and central grooves.

Horixo?a nnd Locn1ity.-Lover Llandeilo ; Tyobry, Penrhyn,Type.-Mrnseniiz of Pract ical Geology (rcg. nos. 16173, 161741).

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CONULARTA LBVIGATA. 1 7Desci.ij~tU>ii.-This species rvas iustituted by Holiii foT tlie receptioii of n

small spccimen from tlic C liasmopskdk (= Llancleilo) of &lcberg; Vestorgtlniid.I t s existeiice in Brita ili lias not , iintil norv, beeil recordecl, biit therc are nearlytlii rty exam ples in Mrs. Gray's Girvaii Colleotiou. Portlook's L'. pzia~l~iszilcritii,va r. Siliiria1-i (Mus. Pr ac t. Geol., reg . 110. 12646), is also, undoubtedly, ancxnmple of this spccies, mhich is therefore represeiited in bot11 Scotlnncl anclIrelaiid.Some of tlie Scottisli specimelzs are p i t e well preservecl ; most are flattened,but one (PI. I, fig, I), slioms approximately a Square cross-section, mcl tliis isprohnbly thc natin4al fo rm , tliougli Holm's type froin Kl labeg is sliglitly coiii-pressecl. Iii tlie latter specimeii also tliere appears t o be a sliglit ineqiinlitybetweeii the pairs of faces, but tliis is not noticeable i11 tlie Britisli forms.I n close juxtq ~?osi tioa it h tlle examples from Craighearl there occur, iii morethan olle cnse, rocls covorecl mitli a sllell exactly sirnilar t o tliat of the Coizz~lrwiz,nilcl taperiiig from a midtll of 3 111m. to tliat of 1min. I h a ~ e een none actnallyattncliecl to tlie Co~ zz~la~ *ia,~ i t thiak it liiglily probable timt they coiistitiitc thenpical eucl of tlie sllell, ~vli ichwas clraw1i out to a con~icle~abl~eilgth, aiid wasprobnbly attachecl to soille foreigii siibstance. The longest lias a leiigth of 25 inin.

r$@ities.-This species is quite clifferent frorn any otlier British form, Itresembles, iil soine cliaracters, the Smedish C, lzvis (Lindstrhni), bnt is reaclilyclisti~~guishecly the horizontal gromth-liaes.Ho~izo7~~ ~ : L ~ z G ZLOC(Xity.-Llandeilo : Crnighead, Arclmillan, a i ~ lBalcletcliie,Girvan. Lower Silnrian : Dosertcreat, Co. Tyroiic.Type,-Geological Surve-y Collectioil, Stockliolm.

Conularia leviga ta, Salter,1866. Colzzcln~ia vignta, .W. Saltei., in Ramsay's Geol. X.Wales, Mem. Geol. Su v ., vol. iii, ecl. 1 ,

p. 354, wooclc. 1 9 (also ed. 2, 1881, p. 562).Diaynosis.-Shell sinall, tapering nniformly ; cross-section rhombic (Y). Tlic

faces mceting a t one acinte angle slightly smaller tllan the other pa ir ; sliglitlyconvex apically and concave aperturally ; apical a,ngle 7'-8'. Margiiial groovessliallow, rounded ; ncinl grooves absent. Apertu re, apex, and ripical septa zin1i:iiomn.Oinnmeiitation absent, except for gently curvecl irr eg~i la rines OE gromtli~

Dinxe~zsio~zs.-Leng 40-50 mm. Width of face 14-15 rnm.Descr2ptiola.-Only tBe ty pe specimeii of this species is knomn, It is somewhat

doubtful m hether tlie ineqnality of t l ~ e ides referred to by Salter is not che t oaccident, and t he coiirse of th e growth-liiles (i, . rising to a rnaximiirn at th e anglewhere the smczller sides meet) may also be a secondary character.. A$ilzities.-This species differs from the other smooth types in the alssence of8

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18 TBE BRITISH CONULARII2E.fac ial grooves aiid in tlie corirse of tlie -orutli-lines. It is possiblele,n tlie absencoof any other enamples, tlint tlie speciinen slioitld be regarded as an ornnmentodsholl, ~ v l~ ic hs srnootli ns tlle result of bad preservatioii.

Ho~izasalil Loccdity.-Caracloc : Lhyn-yr-hmch, Beddgelert, N. Wales.I'pe.-Museiirn of Prnctical Geology (reg . 110. 12657).

Orilasnesltatio consistiilg exclnsively of t ra is ver sc ridges or of trtberclesarrasigecl iii trailsvcrsc rovs, without fiuer loilgituiliiisl ridgcs.

(A ) Interna1 raised longitudinal ribs ("sept a" of Liiidstrni, loc. cit.) pre sen tdem thc centre of eacli face .(n ) Ornamentatioil extremely fine; harclly visible mithont a leiis.(i) Septn in pa irs clomil tlie c e n t ~ e f each face. I-aces ecpd.

T~ ibercles oullcl aiicl clistisict. C. ns11a*sc~, ii~clstrill(ii) Septa in pairs ~ O T P I ~he ceiltre of each face. Paces eqiial iii

opposite lmirs. Tt~berclesnoie or loss coiiflirent in longitii-diild rows. C. ~ I I L ~ L C ~ C L ~ ~ ,p. nov.

(iii) Septa in pnirs domlz tlie ce-iitre of each face, aiid also siiigly a ttlie aiigles of the pyramicl (P). C, sp. cf. n,ye~.sa,

(6) Orizamentation coarse. Septa singly clomiz th e cen tre OE each face.(i) Tiansverse riclges p i t e sinooth. C. ielzlris, sp, iiov.(ii) Ridges finely t~iberciilated. C. t e ~ ~ z ~ i s ,nr. v~aczllosa.

(B) No inter nal lougit~~dirm libs preseut.(a) Orilamentation very fine, j~rst isible to tlie nnked eye or oidy visible

with a lens.(t) Marginal ancl facial grooves vitli prominent edges.

(i) Slrell lai-ge; idges fiiie n ~ l degular, festooiiecl across eachhdf face, C , C O ~ ~ O ~ Z G ~ ~ C L ,p. I ~ O Q .

(ii) SLell small ; idges form a sigmoidal curve from tlis facinlgroove clown to tlie marginal groove.C. xp, ( q 7 t n ~ g n ~ i t e - a)( t t ) Marginal nnd fncial g~ oo ve s imple.

(i) Shell small ; ornainentatiou only seeu under microscopc.C. ntic~os~opicc~,,p. nov.(ii) Shell small; oriiamentation j ~ i s t isible to naked eye.

C. sp .(b) Ornasnentation visible to naked eye.

( t ) Tubercles rouncl ; confined to tlie ridges.(i) Ridges coaiqse, tur nin g up at au angle in tlie marginal

grooves ; faces flat, 0. gzmcl~"i~z~lcoto,owerby.

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CONULARIA ASPERSA. 1 9(ii) Riclges fine, turniiig 1111 at an aiigle iiz the marginal groove,

mcl cilrviiig across tlie face. G, rlefie~icostn, andbwg er.(iii) Ridges fine allcl closely packocl ; aoes coiivex.

C, ylubosn, sp. izov.("f) Tubercles prolonged as sharp projectioils on to the fiirrowabove.(i) T~~berc losval ; projectioils fiiie, curving, liair-like, md

irregiilar iil lengtll, C. I~ispida, p. izov.(ii) Ti-tbercles short, bliiat, ti. ia iig i~ la~.Ridges fiile, andclosely packecl. C. tl*ia~~gzilnris,p. nov.(iii) Tilkercles proloilged iipmarcls as sharp, straiglit lainells,extencliilg nearly across the f i i r r o ~ .

Cr. hnstuta, sp. nov.

Conularia aspersa, Linclstrm. Plate I, figs. 5-9.1873. Co?zzblc(ivia bifcLscinta, J. W . Selter, Caii~l. e~n br. ilur. FOSS.WOOC~JV.US., . 171 ( i~ . 26).1884. Go7zzbla?in asliwsa, G. Liiiclstrom, Silur. Gasixop. Gotlanil, p. 46.1902. Conzda~ia qnscinta, F. R. C. Reecl, Geol. Meg. [4], vol. ix, 11.123.

Dinyl~~osis,-Shell arge, very thiii ; apering iiniforinly. Cross-section probablys p a r e . Faces eqiral, flat ; apical angle ako-tit SO0. Marginal grooves shallow,iilconspicuous ; centrd facid groove faint alzd inconstailt, flankecl by a pair offine interizal ribs, coiivergiilg froi~i3 mm, to less than 125 m m . a t t he a~ex ,marked on tlie exterior by fine klack lines. Aperture nearly closecl. by foart r i a n g ~ ~ l a robes, formiiig m elevatecl cone; apex shaqdy pointecl; apictzl septa~~nlcilowii.Oriiamentation iilcoilspic~ious idges fine, closely packed (40-100 iil5 m.);rchecl gently across each face, meeting a t a, wicle nagle aucl mithoutbrealr i n the marginal grooves ancl iindistizrbecl. by th e central ribs ; stucldecl vi thsinall round tiibercles . Fu rro ws smootli. Growth-liiles folloni tlie coilrse of tlieridges.

Dinte~zsioizs.-Lengtli a t least 120m. JVicZtli of faco, 35 mm.Descr@tion.-The Brit ish species, wbich is coinrnoil in tlle Lowei' Liicllow Flags

of Shropsliire, is iindoUbted1y the stirue as the species frorn Gotlnrzcl described byLindstrm (Pl. I. fig. 8 U). I have examined a large nimber of the Smeclislzforms, and find that they w e quite inclisting~ishab le rorn the British speoiniens,exoep t for tlie Eact th at as a rille the ornm entati on is better preserved. Halter'siiame, b~a sc in tn , s th e earlier, bn t in the Catal. Cambr. aiid Silur. Foss.' nodescription or fignre is given, so tha t it can only be regarrded as a MS. lame mclLindstrm's name, aspelSsa,must be adoptecl.

The " nternal septa, " of Lindstrm ai'e well Seen in almost every example,

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CONULARIA TEITIS. 21layers of the shell, riclging up tlie inner layer ouly (1 I , fig. 11). Tlieorna men ta tio i~ ppears to bc almost iiitermediate betweeil tliat of C. c~,,~yc?~sa,Lindstrm, aild that of C. czu8ta,Sandberger. I n tlie yonng sliell tlie loiigitizdinalriclges w e allnzost strenger thau the traiisverse (Pl. I, fig. 10 ), but iu the adultboth are equally stroiig (P l. I, figs. 1 2 a, 1 2 O). The iurrows we only fine groovesbetweeii ne ighbo iiril~g riclges. Tlie shell is fairly tliick, aiicl consists of twodistinct layers.

-tiflilzities.-This species is closely relnted t o C. sp. cf. nsl~msa rom the B d a ,and to C. CIS~OI 'SCLr01n the Lndlow. It is distiq~ii sliccl rorii botli by the form otlie traiisverse sectioiz, by the small ailglss of thc faces, ancl by tlie orilnmeatatioiz.

I I o ~ - i s o ~ zi ~ dLoca1ii;y.-Midclle and Uppcr Llm doveiy : Woodlaild Point alidPeakill, Giivan.

Ty13e.-Mrs. Gray's Collection.

Conularia sp. cf. aspersa, Lindstrm. Plate I , figs. 13-14.I n th e liighest Ba la rocks of Tliraive Gleil, Girvali, aild at the salne horizou at;

Horde rley, incomplete fragments of a Coiiiilariaii are foinncl. Blthougli speciiuciisare faiily immeioiis, oiily one (PI, I, fig, 13) gives an y clctail o the form of tlleallell, This specimcn, so fa r ~i.s an be ascertaiiled, is tlic exteriial cast of one face,mhicli. tapers unif ormly a t aii angle of al~oii t 5". The interiial longit~iclii~nl epta,"so cl iarac teristic of C. ~ ~ s j ~ e ~ s a ,re also foiiilcl liere, ancl from tlie figurecl speciineliappear to be preseilt, not only in pairs dowii the ceutres of the faces, but also attlie angles of th e pyramid (Pl. I, fig. 13 n). Tliis appearwice msy, homever, bemisleacling, ancl cal-~aotbe confirrned froin otlier specimens, as these, tho~zghsllowiug' the sep ta, arc all very incomplete ancl brolten, No sliell is preserved,biit the ornarneiltation is well seen in tlie cnsts, ancl closely resembles that ofC. nsycqtsn (Pl, I, fig, 1 3 Zi). It varies rni~cli n coaiseness with the size of t lle shell(cf. P1. I, figs. 13 O mcl 14n). Tliis spccies is closely allied t o C. yi inc ta t~~ridto C. nspeysa, from both of whiclz it ~ n a y rovisionally be clistinguished bp thepreseiice of th e septa," a t the allgles of tlie py'arnid.

The figured specimen is in Mrs. Gray's Collection, aud Comes from the Starf ishBed, Girvan.

Conularia tenuis, sp. nov. Plate 11,figs. 1-3.1878. Co?zz~la~ia,p. incl., R. Ethei.iclge, jth, Quslrt. Joiun. Geol. SOC.,01. rxxiv, P. 19.

Diagnosis.-Shell large, very thiu, tappering unifornily; cross-sectioli sqiiare.Paces equual, flat ; apical angle 10-140. lllarginal grooves shallow sncl jncon-

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2 2 THE BRITISH CONULARIB.spiciioiis; centre of face mar1rec.l-edby a conspic~~oiisongi t~~dinaliiternnl " eptuiii."Apertiire sliglitly coiitracted; lobes broacl aiid rounded ; aliex tape rs to a shar ppoint ; ljioal septa imknowii. Omamentatioii liighly characte ristic. Ridges fine,perfeotly smooth, well spaced (5-6 iii 5 mm.), fornling an average angle of 132'along the central rib. Furrorvs smooth or irregularly wrinkled.

Di?7te~zsio~zs.-Lengthait least 180 min. Greatest micltli of face seen, 20 mm.Desc~+?tion.-It is certainly this species to wllich R. Etlieridge refers, loc. cit.,

bnt his specimens seeln to have been very fragmentnsy, aud he therefore gave iloDame and i lo fignre, Over seventy specimeiis have coine nnder rny notice, aiid thespecies seems to be one of the best marlrecl as well as oile of the most interest ingknowli, At present it has only been fo~~nclii tlie dark grey cemeiit stoiic in theLower Carboriifero~zs f Scotlaad, where it is always completely flattened . Fr om tlieeqmlity of tlie faces, ~ l n dhe syinmetry between the halves of each face, it may beinferrecl tha t tlie cross-sectioa was sqiiare. The inost cliai-acteristic feature of theshell is tlie strong median ril2 which is Seen clown th e ceiitre of esich face . Th isri b is of t he Same nati ire as tlze iilte rna l " septum " seen iu C. nsyeysa, but asthe sliells aro almays flattenecl, the rib becoines coilspic~~ouspon tlie oiieersilrface. More ofteu thau not a complicatecl network is seen, for ow il ~go tlie tliiil-iiess of the sliell ancl the compression which lias occ ~~r red ,lie tiailsverse aiid loagi-tilcliiial riclges of the two under faces are also promineiit upoin th e ou ter surface(Pl. 11, fig. 2). The ridges are smooth, glossy, anti yo~mdecl, ncl are generallytvell preserved. I n the fiirrows the very tliiri sliell is ofteil seeii to be wrinklecl(131, 11, fig, 3).

The most remarkable feature of this species is the close associatioii of sev eia lindivicluals, which has not, to my lcnowledge, been recorded for any otlieil species.P1. 11, fig. 1,shows a t leas t sixteeii speciiilens of varyiiig sizes, attacliecl a t the irapices, and radisting from n ceiitre. This is tlie most nearly perfec t, tho ughnot the only example, I liave seen. I n the Britisli Museuni (Nat. Bi st.) is a slabwith three large specimeiis ancl a foivtli fragment racliatil~ing rom a centre (no. G.17662) anti anotlier vitli at least seven small iiidivid~ials howing radial arritnge-ment (no. 17664). There is no sign of specialisation among tlie iuclividuals, andth e arrangement was, tlierefore, probably no t of the natu re of a tnie colony, butrnerely an associatiou of separate indivichals.

ABnities.--This species is quite unlike any other, owing to the thinness of thesliell, the central iilternal longitudinal iib , ancl the smoothizess of the transversericlges. It is possibly aillied to C. aspe~sa.

Horizo?za n d Locn,lities.-Calciferoiis Sandstone : Glencartliolm, Eslrdale ; Waterof Leitli ; Woodhall Mi11,Type.-Geological Survay Miise~im,Eclinbiirgh.

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CONULARIA CORONATA.Conularia tenuis, vw . maculosa, iiov. Plnte 11, fig. 4.

Five speciweils of the seventy-tmo nhicli I have exaininecl cliffcr froin t l ~ emajority iii liaving the riclges s1iglit;ly vieler, niid tlieir siimmits oinslineiitccl nritlia row of small ronncl tuberclas (Pl. 11, fig. 4). Tlic latter a,re exceeclingly wo11marked over tlie vhole of the shell in tlie specimens in nrliicli they occur, ancl asin thc comrnon ty pe thcre is not tlie least trace of tubercillation, tliese fern examplesconstitiite a mell-markecl variety. I n d l other cliaracters they agree witli thenormal type, except, perhaps, tliat tlie ridges form a C L I ~ T T ~ cross tlie face rathertliail a sharp angle along the ceiitral riclgc; bnt this clifference is not stronglymarkecl.Conularia coronata, sp. nov. Plilte 111, fig. 1.

Diccgnoo.is.-Shell la'ge, very tlliri, non-calcareo~is tn~c 'ing ulliforiiily ; cross-section a flattenecl rhomb (T ) ; faces equal, flat ; apical angle about 15". Mrtrgiilalgrooves well defiiiecl; eclges becolizing prominent towards tlie nperture. Similargrooves mit11 raisecl edges ~iln~kiiiglie centres of the faces; half-faces w ai n s~ ib -clivicled by fine seconclary grooves. Aperture i i n k n o ~ ~ ~ n ;pex pointecl; alsicd septanot seeil. Oinameiltation inconspic~~ous-only sec11 mitli a lens. Ridges very finc,regular (75 in 5 mm.), form ing a series of festoons across the face, rising irregnlarlyat tlze inargiiial ancl central grooves, nncl falliilg in shallom arcs between; growtli-liiies folloming tlie cowse of th e riclges. Riclges brokeiz iip by vertical striations;f nr ro vs smooth.

Dinze7~sio7~s.-Length of largest specimen (incoinplete), 107 mm. Greatestmidtli of face, 32 mm,Descq*@tio~%.-Onlymo exnmples of this species are knomn, mcl each sl.ioms agreatly crumpled ancl ~v~inkledi~rface, ointing to a very thiii, probably non-calcareous test. Plate 111,fig. I, shows tlie more uearly perfect of the two, biit tl ~ i salso Iias only three faces preserved, is greatly ~omp~essecl,nd sliglitly cleformed,so t l ~ a the cross-sectioii is doiilstful. The prominent raisecl eclges of the margiimlancl centra l grooves, so mell Seen in this species, are of frequent occurrence amongtlie earlier C o u i i l a i ~ , ut are never Seen in tlie lateil f o r m . The fiiie and bea uti fiil l~regu lar orilarnentation is best Seen on tlie i*aised eclges of tlle grooves (Pla te 111,fig. 1 b), mhere tlle tes t is less wrinkled, bu t can be traced across the crnmplcclsurface of each face. Th e coiirse of tlie ridges is somewhat irregnlai. ; they risea t each marginal ancl ceiltra l groove, biit the lieight t o which they rise and thcsharpn ess of tlia curves formed vary consiclerably on the different faces. Theridges appear to be brokeii iip by a very fine cross-striation, of nhicli there is notrace in th e furroms.A$hities.-This species resembles tlie early smootli types superficially, bu t is

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CONULARIA QTJADRISULCATA. 25defined ; edges sliarp ancl base 'oiincled. Pacial grooves cleep, straiglit, cen~ral.A ~ e r t i i r e ilknonrii; apex sharply poinlecl; apical septa ui~lriiowu. Oriiamentatioiionly seen uuder inicroscope. R i~ lg es ery fine a11d closely ti~berclilatod 250-300iii 5 nim.), for'miiig an ailgle of 1-45"-150" aloug the fm ia l grooves, ceasiiigabriip tly a t tlie inargiilal grooves. Br'o~vth-liiies ollowiilg tlie saine corirse as tliericlges, ancl visible to the iiakecl eye.

Dime7zsions.-Leilgth, 20-30 mn, Greatest wicltli of olle face, 5 iuilz.Descviptio7z.-Tliis small shell appears perfectly siilootli wlieii Seen with th enalred eye, biit iriider liigh magilification the very fine, aiid ofteil well preserved,oriiainentatioi i is ~vvell seeil (Pl. 11, fig. 9). Tlie vertical striation, seen on theridges, does ilot appear to extead to the f~ i~ ro rns . lie iizctrgiiial ancl ceutralgrooves slre qnite smootli.

4gilzlties.-Xomc specilneus of tliis shell iniglit be inistalceil for the smootliorexarnples of C. l i ~ ~ n a ~ * s s o ~ ~ i i ,ut ulider the lnicroscope tlie ornameatation clistiii-guishes it froiu that aucl a11 otller fo~ms. It is probably alliecl to C. corai%utn.

ITo~izon ~u.dLoccdity.-Wei~lock Sliale : Biiildmas.1'ype.-~Iusei1m of Pract ical Geology (reg. iio. 1 2628).

Conularia sp. Plate 11,fig. 10.Dic/,g~tosis.- Shell sindl, iaperiiig uiliformly ; cross- sectioii sqLraYe. Paces

equaall,lat ; apical angle 15". Marginal grooves mell clefined, ro~iilcled, airly deep.Pncia l grooves ceiltral, fiile. Apertiire, apex, a11d apical septa uilkliowil.Oriiameiitatioil iiicoilspic.~roirs; idges fiile rtud close (25 iii 5 mm.) foriiiii~gaiiangle of 130" aloiig tlie facia l groove. Ridges uearly as wide as the ffnrroms;t~~berciilatecl. urrows smootli.

Dinzel~sio7zs.-Leiigt11, 25 mm. 2 Wicltli of face, 7 iilin.Desc~ipt.ioq~.-Theie is oiily oue exawple of tliis sinall form, aud as t l ~ e

preservatioii is no t very good, ancl only orie comlilete face is seeii, I have not nainedit as a sepai-ate species. Tlie inost markecl cliaracters are tlle s p a r e cross-section,roiri?decl niarg iiial grooves (Pl.11,G g . 10 b) , allcl fine r'idges syn ~m etrica lly lisposedal o i~ g he facial grooves. The firier orua~n euta tion s almost obliterated, but theiIclges alipear to be tuberculated (W . 11,fig. 10 C ) .

Afi~zilies.-This species is iiearly alliecl to 0. ~iric~asco~icc~,rom wliich it isdistingtiished by the much coarser ornmeutatioii.

D(1~~izo7ziqlcl Locality -Weillock Limestoile : Leclbiiily.Type.-British M~rsenin Nczt. Bist.) (reg. no. G. 117'38).

Conularia quadrisulcata, Sowerby. Plate 111, figs. 2-6.1821. Conzdavia puacl~isuZcata,Some~by,Min. Concli., vol. iii, p. 107, pl. 260, figs. 5, 6.1840. Co~~uZariauadrisalcatu, J . Prestwicli, Trans. Geol. SOG .2 ] , vol. V, p. 442, pl. d,ig. 2.

4

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i THE BRITISI-I CONULARIA,1849, Comdaria qzcadrisz~lcata, . Portloclr, Rept. Geol. Loiidoiiclcrry, p. 393, pl. xxix A, figs. 4, 5.1847. Colbulavia tube~icostn, . StLiiilberger, Neues Salirb. f r Mineral. etc., p. 21, PI . i, fig. 12,1855, Co~i;uZai*iat~nd~istclcata,. M'Coy in Bedgwiclc's Syriops. Bi it . P:~l~oa.ocl~s,1.520.1873, Co?l~~lavialavus, J . W.Salter, C&d. Caiilbr. Silur. Fo ss, Woodw. Miis., p , 153.1902. C o ~ ~ u l a ~ i a~UVT I , , ~ , . E. C , Reecl, Geol. Mag, [4], vol. ix , p. 122.

Dingimsis.-Sliell vai+ies iiiucli iu size ancl talieils iiniformly ; Cross - sectionSquare. Paces e q ~ i J ,lat; apicd angle about 14'. Marginal groovcs wo11 inarkccl,ivitli angular base aiid eclges ; fscial grooves inco usta~ it. Apertiire liaitially closcclby four sbost lobes heut dowii at rig ht aiigles to tlic axis; a p ~ xhar,i.yly goilitccl;apical selita rarely seeu, geutly convox. Ornaiiientatioii increasing in coarscnessiv it l tlie increase in the sise of tlie specimen. Riclges well defiiied; iii niadiiim-sized syeciinen (Pl. 111, fig. 2) 8-10 in 5 mrn. ; foriniiig ;m eversgc angle of 140'across the fsce ; stizdrled witli small ro~iiicl uberc les, Fu rro ~v s iliooth.Dk)~ensioi~s.-The mgest specirneil is csllc~ilatecl o be over 200 iiiin. iii leiigt11.Greatest .vvicltli of face, 36 inm.

Dcsc~e1ti07~.-Tlie ilaiile pundj.iszJcnta was t he firs t specific name giveii bySowerby, aiid is geiierally recognised to Iiave iilcl~ided noro t h m olle form fr o ~ i imore tlim olle liorizoii, Iii 1845 tlie namc. was restric icd by cle Verileuil to tlieCarboiiioroiis form, mcl silico tliat tiine it has beeil appliecl iiicliscriininattcly tomost Csrboiiiferous species; but eveii wlieii iestrictecl the species is a very variableolle. Tlie Coal Measure foriils, froiii tlieir sta te of preservatioii aild geiierczlappearaiice, ~vo~ilclecm to be qiiite clistiiict froili tlie lnrger liiziestoizc specimeils,but vlieii tletails aye preservecl oil the lzltter tliey are foniid to sliade quitaiiisensibly into tlie foriner. The sise varies ii1ziiieiisely; probably tlie smallestsliolls ere iiot full gromn. On tlie ~vliole lie Coal Measiire exaiuples a re sinall,fen exceecljiig a lengtli of 60-70 111111., ancl iionone reachiiig the l arge sise of tlieCa~lioiiiferoiisLiuiestone forins. TLe appeal1aiice of tlie oruaiiientatioi i variesg e a t l y accorcliiig to tlie sta te of prestc~vatioii. Iii specimens from a coarseliuiestone iio sle ll is seeii, aiiil tlie ridges appeai3 broacl an ti rougli, ~v it li nly afaiiit iuclication of tiilierculiltioii (11. IIT, fig. 2), while specimeus froni tlie iron-stone iiodiiles of tlie Coal 1Measiires sl iov n delicate ornaineiilatioii beaulifiillypreserved. Iii tlie lat ter two clistinct lityers of shell may be seeii. Tlie innermostis very tliin, light-coloiired, oliaqie, aiid little oriiaiiieiit,ecl (Pl. 111, fig. 4 b ) .Outside tliis is tlie tliiclcer layer, which is iuost ofteil seoil, aiicl. 1v11icli in tlie iron-stoiie specimciis is dark brorni to b l ~ c k , eini-trauspare iit, and witli a resiliouslus tre . Tliis, mlieii perfectly preservecl, shows be a~ iti f~zlouudecl tnbercles oa thesiim nit s of tho riclges, witli tiny projections passing from tliem to th e base of tlieridge in the clirection of the apcrt iire ; tlie fumows are qiiite srnootli (Pl.111,fig. 5 ) .Occasionally, as the result of ~ e c o n d a ~ yctiou, tlie furrows a re throwii iu to a seriesof irregular iuterlockiug folds or corrugations, whicli a t times assiime a more orless reg~dwarrangcment, giving the effect of a noi3mal lougituclinal striation

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CONULARIA GLOBOSA. 27(obscrvecl iii otlier species, biit not so frequeiitly). Tlio arrniigeiiieiit of tlleridg cs in tlie inargiiial p200ve is very cliaractci-istic; on t l i u erlges tlicy tivii iipabri iy tly to~ ~a rc l shc apcrt iire , aiid meet, oia dteri iat c, nritli tliose of ilic acljnceiitfaco a t the hase (Tl. 111, fig. 2). Soinetimes tlie riclges hifii~cete n tlie edge.~!t)i?~ities.-This species is qiiite iinlilre xiiy o tl ~c rBritisli. form. Tlie coarserspccirneiis fro m the limextoiie sornetiixies sliglitly reseinble specimens of C!, cmssn,l ~ i i tliey ai3e read ily clistingiiished by tbe oriiaiilentation of tlie iilarginal grooves.

IIo~izoas n ~ ~ c locti1ities.-Uppcr Devoiiiaii : Pradkinawh, N. Devon (pare).Carboiliferons Liiiicstoile : Yodcslrire, De~b js li ir e, taff ordshire, Dulijlii~,Glasgow,etc. Goal M ea s~ i~ esConlbrookclale, ctc.

Conularia deflexicosta, San i lbe~gerY ).1847. Conz~ln~iaZcjZercicosta, F. S&liclbcrgoi.,NFucs Jahi.11. fiir M h . , etc., p. l ( j , p1. i, fig. 6 .1S9G. Conzrlcwicr. dqfle~icostci,G. F.Wliiclbonle, Devon, Fn~iiitt .Eii~lr~lniid,ol. iii, p. 35, pl. iv, fig. 13.

Rcwtnl*lcs.-In tlle monograpli referrecl to abore TVhidborile clcscribed a veryimpcrfcct speoimen of a Conulariai~rom Filtoil, ancl refcrrccl it, "prcsnmptively," toS;tizclbcrger's xpecies, C. de; f lcx icost t r . I h w e not seeil nily otlier sim ile ~ pecimens,so tli at the occiirrciicc of this specics iil Britein reinains cloiibtful. Tlie riclgesappc:1,;1 to be tiibercnlatecl ancl the fiirroms smootli, so tliat tlie species mu st beplaced in tlie sectioil Moili1ifei.x.

Conularia globosa, sp. iiov. P1. 111, figs. 7, 8.Diccgloosis.-Sliell of inecli~imsize, tapcring iiiliformly ; cross-section a s p a r e

witli the sicles coii~rex. Faces equal, gently coilvex; apical angle 7"-8".Margin al grooves of mediuin dcp tli ancl mith roanded base. Facial groovescen tral, fei nt, oilly seeii iii yoiiiig specimeils, Ape iturc ~mliiiown. A l~ical ep tiin ~cleeply convex, vi t h circular trmlsrerse section. Ornamentation fine. Ridgesproiniiieilt, crowciecl (25-35 in 5 mm.), forrning a very wide angle 01%broacl ciirveacross the face, arid coatiiinoiis across the mmgiilal groovc, inaking an angle ofil13oiit 140" i n it s base ; closely stiiclded mit11 small round tnbercles. Fur rowssrnooth.

Dinzcnsiolzs-Length aboiit 10 0 mrn. Greatest midtli of face, 19mm,Desc~z$tiola.-Of tlie two specimeiis Bno~m, nc (Pl. 111, fig. 8) appears to be

qiiite a yoiiilg form. Ea ch shoms the trne cross-sectioil, and tlle cliarncteristiccleeply coiivex septiiin. The riclges are very close togetl~er, specially tomarcls .tl le ap w' t re ; tliey are for tlie most part regnlar, bitt in places aiiastoinose, anclva ry the ir coiirse. Tlie tiibercles are well preserved orer tho mliole shell, ancl nosign of ornamentstion is seeii in the f~u~o mrsPl. 111,fig. 1 ) .

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TEIE BRITLSH CONULARIAE.~jfiil"iies,-Tllis s~eciess most iieai*lyalliecl to C. qiic~clridcntn, rom mliiclz it

is distinguished by tlie coiivex faces, tlie deeply convex sel~tiim,aiid tlie fineoriiameiitatioii.

Ro~i~all,rud Loctlli ties.-Cai.bo1iifei.011~ Limextoizc : Avoii Gorgo a,nd Tortm~oitli.LTgpe.-Miiseiiiii of Practical Geology (reg. no. 11909).

Conularia hispida, sp. nov. Pliite 111,figs. 3-11.Dir/gnosis.-Slzell of iiiedii~m izc, tliiii ; aljering ui~iforiiily ross-sectioii sc~iiarc.

Faces equal, f l n t ; apical angle 10"-12". Marginal grooves deep nild nnrrow ;11nse arid sicles ro~iiided. Facial groove fii~e , ceiitral. Aperture, apex, aiidapicnl septa unlriiom. Orna1uentation fine ; traiisuerse riclges (8-24 izi 5 mm,),foriniilg $11 aiigle of 130"-145O along thc ceiztrnl groovc ; closely st~idclecl vitlism dl pew -sbal~ed tubercles, mbich wre proloiigecl upmarcls as fine pi.ojcctionsabout half vay ~ C I ~ O S Slze fiirro~v lie ot,l-ierhalf qnite sinootli.

Di~~~e~~sio~zs. - l~eizgt l~boiit 140 inin. Gileatest ~vicltli f face, 25 111111.Desc~~i~~tio~a.-Tl-iisliell is usually foii~lcl somewliat compresseed, but olle

specimeii froizi Ledhiry gives a truly sq~m re ross-section (PI. 111, fig. 10) . Tliestate of preservatioii is goocl ailci t411e characteristic orilamcntntiorz is well seeii.The riclges (average, 14 in 5 inm.) wre more closely packed 11ear tlie apex, and passwitlzout a brenk across tlie innrgiiial grooves. D o m tlie centre of eacli faco thesbell is pilclcerecl into litilc sliort folds, nrliich follow tlie coiirse of tlie ridges, aiiddie out before reacl~ing lle inargii1~1 rooves. Tlie litkle pear-sliaped tubercles(45-50 in 5'iniu.) are often miich worn dorvii and nearly obliterated, biit mlieii~ e l lrcserred are seeii slightly clasl~inghe ridge, aiid ta,pe~irig ipwards iiito finepoints (Pl. 111, fig. 11). Tlie upper half O E each fiirrorr is p i t e smootli.

ALtfiiiitles.-Tliis species is reaclily distiiigiiislied froin any otlier hy it,s uniqueornamentation.

Hol i zun nq~dLococ

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CONULARIA HASTATA. 29Di~~~,el~siolrzs.-Lengtlit, least G0 inm. Greatest widtli of face, 14 inin,Desclr.il~tioqr,-Oiily one example o tliis species is lriio~~rn,iit its charncters me

so vell mai~lceclas t o justify its separation as a new sliecies. SIie sliell is mcllpreservecl, ancl 1ias niiclergone oiily yery sliglit clefonnatioii. Tliis lins resultecl iiitliree of tlle faces being sliglitly ibidgeddown tlieir ceiitres, bnt tlie foiirtli shoivs afine groove, mliicli is probably the na tural conditioil. Tlie ma17ginal grooves arealso probably a trifle cleepeiied, biit in places show a geritle, roiiiidecl base milli tllcornamentation coutinmng across ~inClisturbecl(Pl. 111, fig. 12 C). Tlie traiisverseridges aile so cromcled as to be liarclly visible to tlie nnkecl cyc. They xre stiiddeclwitli close-set tnbercles, roiiiiclecl below, bnt 011 tlie iipper side proloilged iiitobliiilt points, which cross tlie fiirrow above (Pl. 111, fig. 12 d ) . Tlie tiiberclesarc fo r tlic most part recli~ced o small triaiigi~ laiiollows.

A.jhzities.-Tliis species is reaclily c li s ti ~g~ii s le drom all otlicrs by tlie fine,close-set ridges aiid the triangular tubercles.

Ho~ixon lzd Localit,y.-Wenlock Liinestone : Diicllcy.Type.-Britisli Museum (Nat. Hist.) (reg. no. 866).

Conularia hastata, sp. nov. Plate IV, fig. 1.Diayzosis.-Sliell of inediilxn size, ta lle ri i~g liiifornily ; cross-sectioil probablg

Square. Faccs eclual (T), flat ; apical ,zilglc aboiit 18". Marginal grooves sliglit ;base ailgnlar ; facial groove fine ancl ceiitral. Apertiire, apex, ancl apical septannkiiomi~. Oriiaiilentation fiiie ; ridges lfiomineiit, closely paclrecl (20-25 in5 mrn.), forming a broacl curve across tlie face, flat iii tlie ceiitre, ancl fdli iig to tliemarg ina l grooves, mliere they nieet the ridges o tlie acljaceiit side n t an angle oflicarly 90". Stiiclded witli very srnall, roinild, distaiit tiibercles, froin mliicli fine,sliarp l a i n e l l ~ xtend iipmards across tlie f~irrom .

Din~.e~zsio7~s.-Lengtl1,0-70 mrn, Greatest widtli of face, 17 min.Desc~.G~tioj~.-Tliere rc s is speciineiis of tliis species in the Snrvey Collectionat Edinburgli, d l f rom t lie s m e locdity. Noile are at all gerfect, and no cross-

section caii t,lierefore be obtained directly. Tlze ouly eviclellce as t o its form istli at affordecl by tbe coiirse of tlie riclges. The l at ter are, in inost cnses, verynear ly symmetrical npoii eacli lld f of the face, mlicli is usiially oiily the cese withsqiiare specimeiis. Homever, tliis is not a certain test, and t l e natural form mayhave beeil flsttenecl, Tlzo oriiainentation is very constaiit for a11 tlie speciinans.Tlie riclges vary very little in dist~ibntionfrom apex to aperture, aiicl downtlio mhole lcngtli OE tlie sliell thcy are fiiie, closely packed aiid very mell defined,ancl t lie l it tle vertical s t r i ~ re iisiidly clearly seeil, especially iii tho exteri~alcasts (Pl. IV, fig, 1d).

Afin.ities,-This sliell sl ig l~ tl yesembles C. llispida aiicl C. I~icllzgu7~~1*is,ut iseasily ~listingnishecl rom both.

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30 THE BRITISH CONULARIITE.Ho~iznsiarl Loralit?/.-Upper Liidlorv : River Esk belon. IIensl~nwBiiin.l1!1pe.-Geological Survey IMseum, Ecliiibiirg1i ( ~ e g .10. 4623).

Ornmentation ca;izcellatecl, v i t l ~ coarscr trms vc rse main ridges, formiiigobtuso aiiglcs across tllc faces, nnil fiiler ai ~ il omei longitiicli~ial iilgcs co i i i~ c c t ia ~tlie foriner. Oriiaiiiciitation visiblc to nakecl eye.

(,I) Trnilsverse sectioii scluare. Longitucliilal riclgcs feeble aiicl iiicoiistant.(i) Ridges coarse, irrcgnlnr, almost liorizontal. Ceiltral facinl groove

stroag. C. eZolzgntcc, Portloclc,(ii) Sliell sinnll; riclgcs a11cl tiibercles fiile ; loiigitncliiid ridges cliiefly

inarkecl oii eithc~icle of tlie marginal grooves.(I. ilicrc,t(i, sp. nov.

(iii) Shell largo ; ridges ancl tu bercles very coarse ; 1-tiargiaal ggroovesvery wide ancl shallov. C. C ~ ~ C I S S ~ ,p. 110~~.

( i r r ) Marginal grooves mi tll ronilcled b ~ s erid proiliiuei~t, inootl~ ,ouacledcclges. C. sp.

(11) Trnnsverso section rlioinbic or elliptical.((1,) Longitiidinal 'iclges fnint m d in co nf it a~ ~t ;npcring morc rapid at

the apex.(i ) Pacid groove mell marhecl, often sub-ccntrd; fiverage angle of

ridges l U O O . Riclges fall inore sharply to tlio '

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CONULARIA PLTCATA. 31(iv) Sliell large ; aliical angle of face 16'-20'; apical se pta

cowex ; riclges ceasc a t tlie edges of tlie mnrginal grooves,which are sinootli ancl nar row . Oruaiuentation as in C.sozilel*Oyi,b ~ ~ toarsc~. C. O ~ c ~ ; i c o ~ ~ v o ~ ~ t a ,p. uov.(V) SScll si~ia ll apical angle of face 8'-10'; apical septa coiivex ;ridges ncarly lioriz o~ ta~ lcross the central ma rgii~al r0ol.e ;criianieiitatioil fi11e ; longitiidiiial riclges ii~~meroiis,l i a r ~ l ~ilefiiiecl, not in coii tnct laterally. C. e i t p ~ s , p. iiov.

Conularia eloiigata, Portlock,

Dilig~rosis.-Sliell siliall, tapcring uniformly; cross-section sclliare. Paceseq ~i al , liglltly coiicave ; apical aiigle aboiit 10". Xlargiual ggroovs wide anrl verysliallow. Facial groove st'roiig, ceiltral. Ape rture, apex, a i d apical septaunknown. Oriianieiitatioii coarse ; traiisverse riclges irregnlar (8 iil 5 miii.),passing horizoiltally slcross the face; interriiptecl by tho fslcial groove, bitt cou-ti i~ uo us cross tlie marginal groove, iii lvhicli they w cli domn to~ va rds lic apex.Furiows crossecl by fine, ieg~ilar,oiigitnclinal s t r i ~20-30 in 5 rnm),Di7~ze~~sio1~s,-Lcilgtliboiit 40 niiii. Grea test wiclth of face, 10 mm.

Dcsc7.iption.-Tlie type speciineil st il l reiliains th e only Iriiowil exarnple of th isspecies. Tlie slicll is iiot prescrvecl, but the ornamentation is fairly well seen,The ridges are irregular aiid tliickened by frictioil, so th at they appear over most oftlie shell more like tlie roi~iicleclgrowtli-liiies of C. l,iln~n~~ssoni,iit towards tlieaper tn re they are fiuey, aiicl as inaiiy as 15 in 5 min., ancl the loilgitiidiual striationof t lie f~ir iow ss seeii to extencl to tlie riclges.

~1 .nit ies. -Tl iis slsecies resernbles C. 1~:s~~~ci~~ssoniii the strongly niai*kedcentralfacia l groove aizcl tlic horixoiital tr ai~sv erse olcls, bu t is reaclily clistiugiiislied bytlie cancellatecl oriimentation ancl the siilall angle of tlie face.

.Uorizou a ~ v l ocnlity.--Cwadoc (3) : Desertcreat.~ y ~ ~ c ~ - M n s e ~ ~ i i if Practica l Geology (reg. no. 12642).

Conularia plicata, sp. nov, Plate IV, figs. 2, 3.Diagr~osis.-Shell of inedium size, tapering nniforinly ; cross-sectiou Square.

Paces equal, flat ; apical angle 1.6'-17". Marginal grooves of medium d ep t l~ ns1micltli ; acial grooves abseut. A per t~ ir e artially closcsd by short Blunt triaugulai.lobes, a t riglit aiigles to th e lnaili axis. Apex sharp ly pointecl; apical septau n h o w n . Orna,mentsltion fine ; riclges fa r apmt (9-12 in 5 mm.), forming broad,

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82 THE BRITISH CONULARIB.simple ciirves across tlie face, continiious across tlie muryinal groove, stiicldeclwibh srnall, rouiid, well-spaced t nb e~c les . F u ~ r o w s ma~lrecl. by secoiicla~ytrmsv erse riclges aiicl faiilt loiigitudiiial striations-tlie la ttor osl~ccially ~iarlccclclose t o tlie inargiual grooves.

Dime~~sio~~s.-Leilgthometiines as muclz as 70 inin., us~zally 20-30 inin.Greatest miclth of face, 20 iim.

Desc~*ij~kio~z,-Tlliss a ~vell-mnrkecl species, of whicli i l ~ e i o are severalexmy3les iil Mrs. Gray's Collectioii. Tlie most cliaracteristic featnres are tliebroad smeepiilg cixrves wliicli. the riclges malre across tlie face, tlle secoiiilarytra i~s versc iclges, and th e s l ~ i d l lista,~it tiibcr cles.

J$Gzit.ics.-This species is easily clist ii~g~iislieclrolii otller cniicellate f o rn ~ s y6i tlie sclume c~oss-sectiona ~ i d iiie ciirved riclges. Wftli C. c?-ci,ssn i t fornis a

t~a nsi tio il et~veeii lie Mouilif e r 8 mcl t l ~ C u i c e l l a t ~ ,11ol"iizoi~ .nS Locality,-U-ppor Bala (Starfisli Bed) : Girvan.T~~JL-MYs. iay's Collectioii.

Condaria orassa, sp. iiov. Plate IV, figs. 4-6.Diaynosis.-Sliell large, taperiiig uniformly ; cross-sectioii a square, witli tlie

sides gently coiivex. Faces equal, coiivex ; apical angle abo~it16'. Margirialgrooves very shallollom, wicle; facial groove 1i;trclly perceptible . Aperture , apex,arid spical septa iiiihnown. Oiuamentation coarse ; transverse riclges stroiig,~videlyseparateil (5-6 in 5 mm ,), form ing an mgle of abont 140" clomil t11ecentre OE the face, st~ ~d de tlith large roundecl, distant tubercles (8 in 5 mm.).

Bimo~~sio~zs.-Le~igtllt least 120 iniu. Greates t wiclth of face, 24 um.D es a, ip ti oi ~. -E xq le s of this species are fo~iiicl in a fairly good stat e of

preservation, often retaining a coiisiderable portion of tlie shell. 'I'liey haveusnally ui~cler'goiie flatteiiing, so thczt the cross-section is obscure, biit onespeciinen (Pl. IV, fig. 5) sliows a broacl ellipse, whicli apperirs to liave beeuclerived from a square, the sides of whicli a re replacecl by gen tly convexcurves. The most marked cliaracter of tlie species is tlie exccedingly wide anclshallow marginal g.rooves, whicli are of tlie nature of gentle und~~lat ions ,itlioutazly well-marked bonudaries, The ornamentation is continued across themwithout any break. The appearance of the ridges ~ a r i e switli the state ofpreservation. Sometimes th e blunt, roundecl tubercles are clear ly Seen ; but morsoften they appear flattened and pierced in tlie centre (PI. IV, fig. G li ) ; or, aPiii,o r i i y . ~aised, wavy riclge may be Seen (Pl. IV , fig. 4 li ) ; or, lastly, the tuberclesmay be woro a~vay nd represented by liolloivs, bet~veeilwhich little portions oftlie shell still remain. The fu rrows are crossed by very slight, inconspiouous andinconstant vertical imdulations.

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CONULARTA SUBTILIS. 33Tlie speciinen seeii iii F1. Iv, fig*4 fi s l i o ~ s curioiis smootli portion of sliell

just belom the fraotiire. On each side it appears t o be qtlito continiious v i t h tlieinner lcss-decorated layei. of the sliell. In tliis character, and in its textiire, it isqnite similar to tlie apical septa foiind in so many species. On eacli side tlietransverse i idges appear iindistur'oed, biit rZoovc their coi~ rse s very irreguLzr forover 20 mm. Tlie pi1obab1e explanation of tliis is, tliat the sholl mas injused duringtlie life of tlie nnimal, and tb e injiny mas repaired by the g ro~vtli f tlie inner lnyer.

A,fiil~ities.-Tliis specios is readily clisting~iishecl rom otlier Britisll f o r m bytlie very coarse oriiamcntation arid tlie miclc, shnllom, marginal grooves. I n generalcharacteis it resembles G. mltc~~dicn, olin, bn t tlie oriinmentation is miiclz coarser,tlie ang le of tlie face layger , nncl thczt o the ridges smaller tliaii in tlie S-~redislispecies.Eorixon n.7zd Loca1ity.-Ilreiilock Limestone : Dudley,

Type,-British Museum (Nat. His t.) (reg, no, G. 6271).

Conularia sp .Desc~iption -8everal frag mentary specirnens occur in the Llandeilo rocks of

Balcletchie and Do~vliill,mhich should probably be placed in a distinct species,but as there is no example wlilch is at all complete I merely note the cliaracteristicfeatures : Marginal grooves well ma~kedmith rounded base, and prominentroiiiided edges ; acinl grooves absent. Faces ecliial, flat ; apical angle 10"-11".Apex sliarply pointed. Ornamentation fairly coarse; ridges (10-12 in 5 mm.),forming a sliarp curve (= angle of 135') across the face, bending iip again andceasing abruptly at tlle prominent edges of the marginal grooves ; smootli near tlieapex, but finely tuberculated higher up. Purrows slightly striated.

Di31ze?zsio~is.-Lengtli, SO mm. Greatest wicith, '7 mm,Al1 specimens are in Mrs. Gray's Colleetion.

Conularia aubtilia, Salter, Plate IV, figs. 7-11.1821. Conuia~in ~~acl~isuZcata,owerby,Miii. Conch., vol. iii,pl. 260, fig. 3.1855. ConuZa?,ia subtilis, J. W. Xalte~,Appenclix A to Sedgmick's Synops. Brit , Palaeoz. Rocks, p. vi.1855. Colzula~in ubtilis,F. M'Coy, in S e d g ~ c k ' s 9, it., P. 288, pl. i, L, fig. 24.

Ding~iosis.-Shell of medium size, tapering slightly more rapidly at the apea.Cross-section rhombio ; diagonals often nearly equal. Faces equal, slightly co mexapically and conoave aperturdly; average apical angle 13'. Marginal groovesnarrow, inoonspicuous ; acial groove fine; cen tral or slightly nearer tlie cen tr d ''

5

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34 THE BRITISW CONULABII2E.marginal gioove. Aperture, apex, aiid npical septa unl

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CONULARIA PLANISEPTATA. 35L ~ I ~ . ~ I U ~ Lncl Localilies.-Upper Liicllom : Brigstcer ; Beiisori Knot ; Under-

bn;i.ro.m; Uslr, Moizmoiitl~shire Wliitclifl, Ludlow ; etc.Type.-Sedgwick Miiseunz, Cambridge (reg. no. ?J 59).

Conularia complanata, sp. nov. Plate IV, figs. 12-14.Di i lgi~~~i~.-Sl ie l laigo, tape~ingmore rapirlly iiear tlie allex. Cross-sectionan cllipso. Frbces equal, gently convex; apical angle aLoi~t15O, bnt the sidesiiearly ~iara llel , xcept tow ucls tlle aliex. Mai.giii~~1rooves shallow, ~vitl imgnl~ i r

base ; ctcitd grooves t~bseilt. A p e r t i ~ ~ e'~nlcizowii;pical septim coilvex, shallow.Oiiiailieiitation fiiie; ridges Iow (17 iii 5 ~iiiri.),foriniag aiz augle of about160" t,o~varclslie aperti~re,cliininishirig. t o l J ? O O tomarils tlle apeu; studdecl withsiriall, rouncl, proiniiien t tiibercles. Furrows smootli, or moTe often sliglltly striated.

Di~?ze~~sio~zs.-Leiigthbout 150 iniii. Greatest wicltli of face, 25 mm.Dcsc~*i21tio1z.-Iiz Carboiiife~oiis ocks tlie species is coii~parativelyabiinilant,bu t i ts preservntioiz is nearly always bad. Tlie shell often reaclies a large size,aizcl t l ~ e risrnatic forn i towarcls tlie apertu re is wcll seeii. Tlie spaciiig of thericlges is very iiiiiforilz for tlie greater pailt of tlie sliell, but near to tlie aperturetlie ridges becoiue very crowcieci. Tliere is a11 imperfcct specimen froni theDevoiziaii of Paclstow, Uornwall, ~vliicll ilay belong to this species (Rritish Miiaeiim[Nat. I-Iist.1, G. 8229).A.fi~zities.-Tlzis species reseiiibles most closely C. sz~Dt.ilis,from which it isclistinguished by tlze large size, thc ~bseilceof tlie fczcial groove, ancl tlie wideangle ol the transverse riclges.

Tlzere is a specimen in the Britisli IIuseurn (Nat. Hist.), reg. no. G. 9030, fromthe Carboniferoiis Limestone of Stoilylinrst, Lancashire, ~vhichcliffers from theforegoing in some iwnportilnt poiiits, biit the pieservatioii is so bad and th especirnea so iiizperfect tliat no satisfrbctory cliagiiosis can be giveii. The cliaracters-cvliich cali be cleterininecl. are : Marginal grooves very shallow. Ornamenta-tion fiile; riclges very iiarrow, evenly spacecl. (14 in 5 um.), oriniiig at tlieapertnre broad curves, wliicli give place towarcls the apes to perfectly straighthor izontal lines, Ridges appear to be ttiberciilated with wiclely separateil rouncl.tiibercles; furrows siizootli. Lei-igth of portion, 82 mm.

Horizolzs mzd Loca1ities.-Devoiiian : Padstow, Cornwall (T). Carbo~zife~ousLiiriestoiie : Bristol ; Oreton aiicl Parlow, Salop, etc.

Type.-British 3111seum (N at . Bis t.) (reg. no. G. 17666).

Conularia planieeptata , sp. liov. Plate V, figs. 1, 2.Dic~g?zosis.-Shell small, tapering iiiliformly, or slightly more rq ic lly near the

npax. Cross-section rhombic or elliptical, with the loiiger dianieter more than

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36 THE BRITISH CONULARIB.double tlle sliorter. Paces eclual, slightly convex ; apical angle 17' - 0'.hlargiiial groove OE mecliiiin de pt l~ , nse rou nde d; facial grooves absent. Apicalseptiim flat. Ornarnentatioii fine ; riilges fairly closc (average 18 in 5 mm.),forming an angle of 145' across tlie f ac e; poiiit of aiigiilat,ioii nea rer to t he

central " tlian to tlie " ateral " inarginal gyoove ; ridges contiiiuous across thegrooves, a t tlie base of wliicli tliey form an niigle of almost 180'; stuclcled witlisiriall, rouncleci, wiclely separatecl tubercles. Piiriows crossed by narrow, well-definecl ve rt icd bars.

Di?lze~lsi07~s.-LeiIgth,0-50 111in, Gieatest vid tli of fsce, 16 mili,Des~1~~~~01t,-Wdl-131'eservec~xamples of tliis small specics are obtaiiied fioin

Tliraivc Glen, biit those fi'oln Woocllaiicl Point are all soinewliat fraginentary. Thefigured speciincn sliows a iiesrly perfect apical septuin, wliicli, iiiilike tlie septa ofinost species, is qiiite flat ; aiicl siiice tlie silrface is qiiite uiiwrinlrlecl, tliis inust b e tlienatural form. The snlsll oblong projectioii iii the centre is ~ e i . y uggestive ofsoine so rt of sipliuiicle (PI. V, fig. 1 ) . I llwe iiot Seen anytliiiig resembliiigtliis in aiiy other exauple, even where tlie septa are ilearly perfect. In tl i isspecimen tlie ceiitral tnbe appews to be closed, aucl may very likely bo only a scarleft by the final con~pletioiiof the septum.

AJhities.-This species resembles most closely C. vcsiczda~is,rom wliioli it isdistinguisliecl by the large ai~gleof tlie face, tlie flat apical septum, ancI s li g l~tdiffercnces in tlie ornameutation.

Horizons nnd Lc al it ie s -Upper Bala and Miclclle Llanclover y : Thraive Gienand MToodlaicl Point, Girvaii.

Type.-Mrs. Gray's Collection,

Conularia vesicularis, sp, nov. Pla te V, figs. 3-6.Uiagiiosis.-Shell of medium size, tape'ing uniformly. Cross-sectioii at tlie

spe rti ire a rliomb with cliameters uearly eq iid , at tLe apex an elliyse or tlie figiire CD.Paces eqiial, flat, convex, or gently concave near th e ap er tuie ; apical aiigle 10'-11'.Marginal grooves of iuediu ii dep h ; f acial grooves abselit. Apical se pt a convex .Ornamentatioii fiile ; riclges moderately close (average 17 in 5 inm.), formiiig anangle of 140r across tlie face; the poiiit of angulation sligh tly nearer t o tlie central"tlian to tlie "lateral " iiiarginal groove ; riclges continuous across tlie margiiialgrooves and fo m in g an angle at tlie base of about 150'. Ridges stiiddecl withrouuded tubercles; fiirrows crossed by prominent bars.

Diaeiisio~ts.-Length about 90 mm. Greatest nid tli oi face, 14mm.Dcscriptio~~.-This specios is of widespread occiirrence in tlie iipperrnostOraovician rocks. Specimens Rre not usually well preserved and no ap erture isknown. TLe " central" marginal groove is usually deeply sunken towards the

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CONULARIA SOWERBYI. 37apex, and tlie Eaces strongly convex, thiis giving an CD-shapecl ross-section (Pl. V,fig. 4 b ) . Towarcls tlie apertiire the " ceiitral l" marginal grooves becolne inuclimore prorniiieiit, the faces become slightly coiicwe, rtnd thc cross-section approacliesa scliiare (PI.V, fig. 4 a).The riclges are geuerally fine uncl ivell-marked. The tiibercles are very ofteuv o r n down, anrl the circular liollows in tlie f~ ir ro w s re tLen strongly markeked(Pl. V, fig. 6 b) . Prequeutly th e sliell is yernovecl entirely, ancl a very cbnrac-ter istic appearance is then obtainecl. Ridges and vertical bars are replaoed bygrooves, and tlie fliri'ows appear to be filled mith rows of gently hollowecl tiibercles(PI. V, fig. G C). I liave not observed this allpeai,i.alicen any other species.

A67eities.-This species is closely alliecl to C. sozae~~liyiild t o 0. ln~~isepfatn.It is distinguisliecl from the la tter by tlle slow rate of taperirig, ancl from th efo rin er by tlie s inalle i ;-rize,aild by the charncteristic ornai~ieiztation.

HOrizo7~ lad Loealities.-Ca~adoc : Acton Scott ; Tynwycl;Cardiiigton ; etc.1'ype.-Mase.~im of Pract ical Geology (reg. lio. 12647).

Conularia sowerbyi, cle VerilerU1. Plate V, figs. 7-11.1821. ~onu la r i a 'uad~isa~lcata,owerby, Min. Conch,, vol. iii, pl. 260, fig. 4.1828. Com~davin owerbyi, Defrance, MS.1839. Ooltz~la~iazcad~isulca ta, owerby, in Murcliion's Silur. Syst., pl. xii, fig. 22.1845. Co.rzulalra sowe~byi, e Terneuil, in M~ ~rchiso li,le Qerne~ul, nd cle leyserling, Gkol. cle 1%

Riissie cl'Europe, vol. ii, p. 348, pl. xxiv, fig. 5 ,1847. Co?tz~lariaancellata, F. 8andberger, Neues Jalirb. f r Min., etc p. 20, pl, i, fig. 11.1855. Colzz~Za~iaancellata, F. M'Coy, in Seilgwick's Synops. I31ii. Paleoz. Rocks, p, 287.1859. Conz~laria owe~byi, owerby, in M ~ ~~ ch is on 'si l i l l l~,d. 3, P. 550, pl. xxv, fig. 10 .

Dic~g?zosis,-Sliell large, taperiilg iiniformly ; cross-section rhombic neai theaperture, elliptical uew the apex. Feces eclual, geiitly comex, apical angle10'-12'. Marginal grooves shallow, bro ad; facial grooves inconstant. Lobeso the apertlne sliort ailcl triaiigular ; apex closecl Isy a convex septum. Ornamen-tation fairly coarsc ; ransverse ridges mell markecl. ( a ~ e ra g e12 in 5 mm., oiecrowded nt the q e x mcl tlie spe rture) , formiiig an average angle of 147". Riclgesclosely se t with roundecl tubercles. Lon git~id iual ars in the furrows twice asnimerous as the transverse ridges, roundecl, aiid in coiztact laterally. Orilamenta-tion corttinuous acyoss the marginal grooves.

Dime~asions.-Length about 120Nm. Greatest width of face, 3 3 mm.Deswiptiom.-This species ia th e commonest of Brit ish Conulariae. It is fo~sndiisually preservecl in limestone, and. la s, therefore, undergone less crushing th anmany. A t th e ape rture tlie cross-section is s rliomb with the longer dimeter

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38 THE BRITISH CONULARIB.rather less than twice tlie shorter (abont 5 : 3)) but at the apex tlle sliell nlrnostinvuiably appears rnore Ratteiiecl, aiicl tlie cross-sectioii talces tlic form of nnellipse witli the longer cliameter more tlian twice the sh orter . Tlie apical angles ofthc faces vary in cliffe re~t pecirnens, bu t tlie measurements are no t ltlways tr iist-ivorthy, and the greater nuinber give values bctween 10-120.

The ape rt~ isa l obes are not usndly seeii, thougl-i there are several specimeiislrnown which sliom tlicm in a rnore or less iiearly coinplete state. Tliey are short,witli geiitlyronnclecl apices, md bencl down at rigl it aiigles to ih e axis of th e sliell(Pl. V, fig. 8). Iii aliiiost all cases tlie sliell is closecl at tlie apical end by a gciltlyconvex septiiin (Pl. V, figs. 7 b and 9) ) micl rarely, iE ever, cloes it tapcr to ,zsharp point, Tlie septum occnrs at varyliig ilistances froin tlie a p c r t ~ ~ r e ,ucL thisfact to the probability of tlie cxistence 01 more tliaii 0110 such partitioii iiith e leiigth of tlie sliell, Incleed, iil one specimaii, from tlie M ~ ~ s e u mf Rirmiiig-hau? University, G nim. above tlie terminal septiiiii tlle sliell is brokeii away, aiicianotller aiid p i t e siinilar sept.~iin s Seen, passing ii~ wa rdsparallel to tlie other,aiid sp p~ e i i t ly ontiiinoiis witli the thiii inner layor of tlie slicll. Tlie orizameiita-tion is of the typicsll cmcellate type. Tlie poirit of ang~zlatioi iof tlle transversefolds is pe'ceptibly nearer to the "colitral" t l im to th e "late ral" inwgiilal grooves,mil the ridges nieeting in the central l" groove from sldjslceilt faces form aii angleapproacliing 180'. I n the apioal half of the sliell the ridges forin straigl lt-sidedclievroils across tlio face, bnt towards tlie apert~irehere is a marked increase i utlie size of tlie angle, and the straight liiies are replacecl by broad, compoundci ir es , at first coiicave, tlheii convex to tlie ap er ti ~r e s tliey pass down from tliepoiut of ang~~lat iono the marginal groove.

The ti~bercles n tlle riclges are sometinies well preserved, but morc ofteii arerecl~~cecly fyictioii t o small roiindecl liollows; still more frequently the riclges are)vorn clown to coarse, roiigh projectioiis, sind iii the furrows betweeil tliese tlic shellis well preserved, aiid tlie olose and regular verEicJ strintiog is clearly seeii. I!th e oiiter layer of th e sl id l is removed, tlie tliin yellowisli unclcr-layer is exposed,ornamei~ted in tlie sa ue way as tlie outer, biit niucli less st rong ly (P1. V,fig. 10 b ) .

Afi?ilLitios.-Tliis shell is tlie comrnonest Britisli representat ive of a ty pe th at iswideiy spread all ?over the globe. It is very similar to the Bolicmim species,C. p?qotcicn, Rarrande, ancl to tlie Sweclish C. ca~zcellata, Lindstrm, biit it isdoubtfiil irhether it is indentical with eitlieiv OE these. Species with strongly can-oellated ornarnentatioii appeaT to bave floilrislied in higliest Orclovicim aud Siluriantimes, aud iluring this period g w e rise to local types (C. plnniseptata, vesicz~lnris,b ~ a r i c o w v e ~ ~ t a ) ,hich cannot be identifiecl with species of oth er 'countriea .s species, C. wiq~cellatn, ran& from the ~r ac h io ~ o d sk if f&o the

rian of Gotlannd, may possibly in the Same way inclucle more tlian onewas not able to identify any with tlie Britiall forms.

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CONULARIA ELEGANS. 39Ilo~izoizs i?dLoc~r1ities.-TVeiilock Liinestone : Malverii ; Ledbury ;Diidlcy ; tc .

Uppei Liicllow : Uiic ler l~a~io~vetc.Type.-Unkilown,

Conularia breviconventa, sp. nov. Plate V, figs. 12, 13 .Ding~z~sis,-Slicll of niedi~ im i z o ,npering uniformlg ; cross-sectioii a flatteiied

rliomb. Faccs oqual, flat. Apical mg le 1Go-20'. Mwgiiinl grooves iiarrom, ofmedium deptli ; fncial groovcs inconstaut. Apcrt~ ire ii ik iio~ ii %Ilex closecl byn, coiivex septiirn. Or iia~ ne i~ta t~ioiioaiae; rirlges, ol