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Unusual in approach and content, this new series will make available in bookform to all scientists the results of some of the finest research and scholarshipin biology. The series will consist of small compact volumes on specializedbiological topics prepared by some of the most outstanding men in the field-biologists, biochemists, biophysicists.Contributing authors will present their findings and views on subjects of theirown research. The series will thus emphasize the personal and individualviewpoints of the authors, who will cover in their books the area of their ownresearch rather than any whole field of endeavor. This in no way limits thebroad scope of the series since the implications of these special areas will influ-ence all fields of science.The Wiley Biological Research Series will enable interested scientists to in-vestigate and become acquainted with special subjects in biology which theymight otherwise overlook. The ramifications of such an approach to originalfields of research in biology will be valuable for future progress and develop-ment.

INTROGRESSIVE HYBRIDIZATIONby Edgar Anderson, recently published, is the first book in this new series.Dr. Anderson is Geneticist to the Missouri Botanical Gardens and EngelmannProfessor of Bsotany at Washington University. He presents in hisi bookmethods for studying hybridization in the field so that its effects in naturalpopulations may be measured. Botanists, geneticists, plant breeders, andtaxonomists who are dealing with the results of hybridization will find Dr.Anderson's di oof the forces at work in such populatin aluable.CONTENTS: Introgression in Iris: A Typical Example. The Ecological Basisof Introgression. sTheGenetic Basis of Introgression. Introgression in FinitePopulations. Introgression and Evolution. Special Techniques forwhie Studyof Introgression.March 1949 1r09 Pages $3.00

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Hundreds of thousands of students of naturehave found in this classic work a key to theunderstanding of the variety and beauty ofthe natural universe. Inanimate and animatenature are covered birds, fish, reptiles, am-phibians, mammals, insects, flowers, weeds,crop plants, trees, streams, water and waterformations, soil and soil conservation, crystals,minerals, magnetism, the stars and theweather.957 pp., over 7000 illus., $4.50 (text edition)

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April~~8,14,Vl 19SINE1

Jnatomy and PVj/i0 y JexliBy

MOSBYt_._st~~~~~~~1DxIntroduction to Introduction toHUMAN ANATOMY HUMAN PHYSIOLOGYAll the essential facts of human anatomy are well pre- In writing this book, the author continuously bore insented, with stress on the function of each part and mind the reader desirous of obtaining a fundamentalon the integration of each tissue and organ of the body. knowledge of the operation of the human body, butB.N.A. terminology is used throughout the text, but having no previous knowledge of the basic sciences ofsynonyms in common use have been indicated. Illus- Physics and Chemistry. By "working from thetrated with meticulous drawings by Miss Helen ground up," this knowledge has been presented in aWilliams. simple but scientific manner.. The physiologic discus-By CARL C. FRANCIS, A.B., M.D., Assistant Pro- sion of each organ or system of organ is prefaced by

fessor of Anatomy, Department of Anatomy, anatomical description.Western Reserve University, Cleveland, Ohio. 472 Students using this text will put it down with some-pages, 313 illustrations, 35 color plates. Price, thing more than mere intellectual acquisition of the$5.50 functions of the human body. As the functions of the

A CONCISE COMPARATIVE various organs are unfolded, it will become a personal-ized knowledge of life-and they will quickly see that

ANATOMY the perfection of bodily functions leads to health andThe material presented in this book is in the simplest happiness.vocabulary consistent with brevity and accuracy. By WILLIAM D. ZOETHOUT, Ph.D., ProfessorTechnical terms are not deliberately avoided-but are Emeritus of Physiology in the Chicago College ofused where needed. Dental Surgery. 424 pages, 138 illustrations, 4Few students study vertebrate anatomy for its own color plates. Price, $4.00sake. Usually it is a foundation for embryology, hu- Synopsis ofman anatomy, or advanced zoological study; therefore,as each anatomical system is set forth, references to PHYSIOLOGYhuman anatomy appear. In this way, the book be- This is a small book designed especially as a reviewcomes valuable to the zoology major and the pre or refresher volume. It covers the high spots of theprofessional student. subject of physiology, providing adequate fundamentalBy WILLIAM HENRY ATWOOD, Head of the material and incorporating advances in the subject.Department of Biology, Milwaukee State Teach- Brief mention of some physiologic disturbances isers College. 413 pages, 303 illustrations. Price, made to emphasize the contrast of normal and$3.75 abnormal.

THE DISSECTION OF THE CAT By ROLLAND J. MAIN, Ph.D., Professor of Physi-(Felis Domestica) ology, Medical College of Virginia, Richmond,Dr. Harrison has had several years' experience in Virginia. 341 pages, 21 illustrations. Price, $4.50

directing pre-medic, pre-nursing, and physical educa- Laboratory Manual for Elementarytion students in the dissection of the cat. This back- Physiologyground has qualified him to present the more signifi-cant anatomical facts in an easily understandable, Fourth Edition. The experiments described in thislogical and concise way. Students using this labora- manual are planned to demonstrate the simpler, funda-tory manual will find it usefulj practical and complete mental reactions of the living organism and the proto-with an arrangement that makes it easy to use plasm of which the organism is composed. Space has

with any text. been provided for written answers to all of the ques-By BRUCE M. HARRISON, Ph.D., Professor of tions; for drawings, and for the kymograph tracings.

Zoology and Head of the Department, the Uni- By LALIA V. WALLING, Assistant Professor, andversity of Southern California, Los Angeles. 109 KENNETH SILER, Instructor, University ofpages, illustrated. $3.50 Kansas. 187 pages, illustrated. Price, $2.25

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April 8, 1949, Vol. 109 SCIENCE 17

April 8, 1949, Vol. 109

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Biochemist; Instructor in Biochemistry at large eastern medicalschool desires similar position at a medical school where he canalso study for M.D. degree. Five years teaching and research ex-perience; excellent references. Box 113. SCIENCE. 4/8

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Plant Scientist and Tropical agriculturist: M.S. in Agriculture,Cornell University. Ph. D. Iowa State College, 1944 (PlantPhysiology, Horticulture, Agronomy). Latin American. 10 yearsexperience tropical agriculture in West Indies. 2 years residencein Far East serving first with UNRRA then Food and Agricul-ture Organization of the United Nations seeks employment in re-search, commercial agriculture or teaching in U. S. or any othercountry. Box 125, SCIENCE. X

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Spectroscopist-Excellent opening for an experienced band spectro-scopist with good theoretical background to carry out directfundamental spectroscopic studies relating to combustion processes.Publications encouraged. Salary open. Write: Personnel Ad-ministrator, Jet Propulsion Laboratory, California Institute ofTechnology, 4800 Oak Grove Drive, Pasadena, California. givingdetails of training, experience, publications, and professional ref-erences. 5-20

Wanted: Geophysicist for teaching and research in active and wellsupported program. Professorship offered to properly qualifiedcandidate. Ph.D. required. Also Stratigrapher for medium-sizedGeology Department. Assistant Professorship with opportunity foradvancement. Ph.D. required. North Central region. Cite ex-perience and references. Box 130, SCIENCE. X

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SPRING BOOK ISSUE0 APRIL 22nd - Don't miss it!

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HELLIGENTESTKITFOR THE QUICK DETERMINATION OF THE ACID.NEUTRAL, OR ALKALINE REACTION OF LIQUIDS

Measuring Range 1 11 pRHellige A.N.^ Testkits ore compact, reliable and inexpensive.

The brilliant colors on the color chort focilitote comporisonsTests cost as little as 1/10 to 1/4 of o cent, depending uponthe quontity of indicator purchased. Wide Range Model No,680 (pH range 1-11) or Short Range Model No.682 (pH ronge4-8), complete of $5.00 eoch, including indicator for 125 tests,

Postage prepaid if remittance accompanies order. WRITE FOR LIST No. 6S0.

ELLIGEINC 3718 NORTHERN BLV~kN *.LONG ISLAND CITY 1.N.Y.

for* MICROSCOPES

* MICROTOMES* REFRACTOMETERSEquipment for Photomicrography

Write to

ERIC SOB co.O 102 West 42d StreetSODEWVA ~~New York 18, N. Y.

20 SCIENCE

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TRANSPARENT PLASTICSPECIMEN BOXES

For keeping small specimens in convenient, orderly ar-rangement, with maximum visibility ahd protection. Veryuseful for passing specimens around the class.

Dust-proof, moisture-proof (edges maybe sealed with Scotch tape), permanent.

Transparent Assembly Case illustrated isconvenient for handling sets of specimens.

THREE SIZES: (Outside dimensions)A: /16" xX /16"x 3/4"tB: 17/"x15/16" x 3/4"C: 17/X 17/"x3/4"

Send $3.00 for assortment #3 (30 boxes-3 sizes)in TRANSPARENT ASSEMBLY CASE, or

Write for Leaflet CE-PBYou will be delighted with theseunique, transparent, useful boxes.

LPCAI ELL 11E Liberty StreetR.P.CARGILLE ~NeW.Yoirk,6, N. Y.

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nntBouncinga new, fullyautomaticfractioncollection

This is the new Technicon Fraction Collector, * apparatusan apparatus which will automatically collect up to200 rigidly controlled samples of predetermined fluidvolumes. Each sample may comprise any number ofdrops from one to four hundred. After the selectednumber of drops have been collected in the test tube,the carriage automatically advances to repeat the iden-tical collection in successive samples until the wholefractionation has been completed, whereupon themachine shuts itself off.The automatic nature of the Technicon Fraction

Collector offers many important advantages.# Sincethe machine will operate continuously without super-vision, it can be run 24 hours a day (and over week-ends) thus tripling the fractionation work output ascompared with an 8-hour laboratory day.- Personnelis released from the tedious, time-consuming operationof cutting fractions, for once the machine is set for agiven operation, it carries on automatically.#Greaterresolution is achieved through the collection of numer-ous small fractions, rather than a few relatively largeones, so that more data become available from a givenfractionation (eg. a chromatogram or a fractional dis-tillation). Dependable accuracy is assured, becausefractionation can now be reduced to a straightforwardmechanical procedure, free of the possibility of humanerror.The Technicon Fraction Collector has been thor-

oughly tested in actual laboratory installations, whereit has proven a boon to busy research staffs. We shallbe happy to send you details on request_* Ref: Chromatography of Amino Acids onStarch Columns-W. H. Stein and S. Moore,(journal of Biological Chemistry, 176, 337[1948]).

TECHNICON CHROMATOGRAPHY CORP.215 East 149th St.. New York 51. N. Y.

an ACCURATE Blood Countis Worth Taking

To aid in correct diagnosis and propertreatment of patients, a blood count -must be accurate. That is why mosttechnicians follow accepted tech-niques with utmost care . .. why they use onlythe finest equipment . .. why the majority choosethe famous Spencer "Bright-Line" Haemacytometer.

BRIGHT-LINE Chambers offerthese 6 Safeguards to Accuracy

GREATER CONTRAST BETWEEN CELLS AND BACKGROUNDCells appcar dark, lines bright, background gray. Each cell is easilycounted-evcn those which overlap lines.

MORE EVEN DISTRIBUTION OF CELLSSurface tension differences between metalized surfaceof chamber and glass surface of cover cause cells todistribute more evenly and chamber to fill'morereadily.I

SIMULTANEOUS RESOLUTION OF BLOOD ...CELLS AND RULINGS

It is not necessary to stop down the condenser of yourmicroscope since blood cells and rulings can be clearlyresolved at full diaphragm opening.

METALIZED BACKGROUND ELIMINATES GLARE %Absence of glare provides clearer vision and reduceseyestrain.

INDENTATION OF UNDERSIDE PROLONGS USEFUL LIFEIntroduction of a slight concavity directly under rulings preventsscratches appearing on lower surface of chamber. Such scratchesimpair counting accuracy.

PRODUCTION TOLERANCES ARE HELD TO THOSE RECOMMENDEDAND SET FORTH BY THE U. S. BUREAU OF STANDARDS

American 1 Optical Whenyoubgyspecify 'Bright-Line" andC .M iA N V accept no substitutes. Immediate delivery

Scientific Instrument Division from your supplier or write Dept. R2.Buffalo 15, New York