298

view wants more explanation, as in one place shespeaks of " a greater proportion of guinea-pigs fromsmall litters in the alcoholic series," and holds that"

any loss of fertility can be equally well attributedto the genetic qualities of the stock itself." Thusit is not clear whether the litters were or were notsmaller in alcoholised stocks. The conclusion inthe report is that there was some deterioration inweight in the descendants of alcoholised animals,which might be due to inbreeding, but the authors hadno control stock to demonstrate this factor. Theyfound that the longer the parent had been on alcoholthe greater the mortality among the young. This

might be claimed as a confirmation of Stockard,but the authors ask: " How much of this risein mortality is due to advancing age it is notpossible for us to determine ... as insufficientcontrol animals of like age were used for breeding."An important part of Stockard’s work was to showthat in the fourth generation an alcoholised stockwas definitely superior to a control stock. The

system of breeding relied on for the report was ondifferent lines from that of Stockard, and so theresults are not comparable accurately.

BIRTH-HÆMORRHAGE IN THE MEDULLA

IT is well recognised that stillbirth and neonataldeath are largely due to impairment of the functionsof the medulla, whether such impairment is causedby pressure from above or local injury. BronsonCrothers teaches that the immediate problem insubtentorial trauma is the estimation of the damage-to the medulla, and he emphasises the fact that ifmuch blood gets below the tentorium the medullamay be embarrassed. It has frequently been

suggested that the immediate cause of death followingtentorial tear with subtentorial haemorrhage is

impaction of the medulla in the foramen magnum.The researches of P. Schwartz have diverted attentionto some extent from gross external effusions to

microscopical intracerebral haemorrhage, mainly inthe subcortical regions and the basal ganglia. Thepossibility of microscopic lesions occurring in themedulla has received less attention. From theresults of an investigation carried out by Dr. F. A.Hemsath and Dr. M. M. Canavan,2 it would appearthat lesions of this kind may be a common causeof death, which may not ensue immediately. Thematerial examined by them consisted of 53 infants,of whom 21 were stillborn, 31 died in the first week,and 1 died of erysipelas on tae 22nd day. In34 of these infants it was possible to demonstratemicroscopic haemorrhages in the medulla, theirincidence being equal in the stillborn and in thoseborn alive. The haemorrhages were present in thefour cases in which the Wassermann reaction waspositive. In some cases a postnatal cause of death,such as broncho-pneumonia, was also recorded,but the notes do not indicate the extent to whichthis may have been preceded by respiratoryinadequacy. These cases may well have somethingin common with the series of infants, described byG. F. Still,3 subject to attacks of sudden cessationof breathing, which could be re-established withoutdifficulty by artificial respiration. The infants werein normal condition between the attacks. In two ofthe cases which came to autopsy there was evidenceof collapse or early inflammation of the lungs, but

1 Disorders of the Nervous System in Childhood, New York,1926.

2 Amer. Jour. Obst. and Gyn., 1932, xxiii., 471.3 THE LANCET, 1923, i., 431.

Still considered that the pulmonary condition wasprobably secondary to a disturbance arising in therespiratory centres. In 14 of the cases describedby Hemsath and Canavan, tentorial tears were found.Ten of these infants had been born alive. In onlyone of them was there any sign of a pressure cone,whereas in six cases without gross effusions therewere microscopic haemorrhages in the medulla.The authors suggest that lesions of this kind mayprovide the real explanation of a large numberof deaths following tentorial tear. They stress thefact that in 12 of the 53 cases in their series thebulbar lesions supplied an anatomical cause of deathwhich would otherwise have remained obscure.The findings are of considerable interest, and invitefurther investigations. They raise important questionsas to the extent to which bulbar haemorrhages in thenew-born are compatible with survival, and theymake obvious the importance-now well recognised-of avoiding all vigorous methods of establishingrespiration in asphyxial infants.

THE PASSAGE OF SPERMS AND EGGS

THROUGH THE OVIDUCTS

THE factors which determine the movement of

spermatozoa from the vagina into the uterus andFallopian tube are little understood. In the rabbitthe swim-velocity of spermatozoa is 0-05 mm. a second,yet living spermatozoa have been demonstrated 13 mm.within the cavity of the uterus 1 minute 50 secondsafter copulation. Computation shows that the swim-velocity would require over four minutes for thisdistance to be traversed. It is therefore tolerablycertain that swim-velocity alone does not explain themigration of spermatozoa from the vagina into theuterus. It is customary to assume that the femaleorgasm causes spermatozoa to be aspirated into thecervical canal. For human beings this suppositionmust be put forward with caution in view of the notinfrequent cases of pregnancy in which penetrationhas never occurred and the hymen remains intact.It is difficult to believe that spermatozoa are depositedin such cases in the vicinity of the cervix ; and againquite often orgasm on the part of the female is denied.The discrepancy between the animal work and clinicalcases is perhaps cleared up by supposing that in normalcoitus aspiration is physiological, but that in the casescited above swim-velocity is the last hope of success-ful insemination.The migration of spermatozoa through the cavity

of the uterus and along the Fallopian tubes is againstthe ciliary movement. This is explained by supposingthat the ciliary current rotates the spermatozoonso that its delicate tail is washed downwards and thehead lies against the stream. The swim-velocity ofthe sperm is then contrary to the current and it isbelieved that the ciliary current can be overcome.This ingenious hypothesis has little experimentalevidence in its favour. For example, if inanimatematter such as indian ink is injected into a livingrabbit Fallopian tube suspended in warm Ringer’ssolution, the material passes in both directions andis discharged both through the abdominal ostiumand the uterine end of the tube. A similar migrationin both directions can be demonstrated experimentallyif living sperms are injected into the uterus. G. H.Parker,1 of Harvard University, offers an ingeniousexplanation for these experimental findings. He

points out that local rings of contraction develop

1 Amer. Jour. Obst. and Gyn., 1932, xxiii., 619.