THE SEMEN. 203 



thra after stool in a healthy man, he had always detected 

 spermatozoa. 



In connexion with the above few remarks on the pathology 

 of the semen, we may refer to the observations of Donne on 

 the effects of an exceedingly acid condition of the mucus of 

 the vagina, and a very alkaline state of that of the uterus 

 itself, on the vitality of the spermatozoa. 



The mucus of the vagina, in its normal state, is slightly 

 acid, this degree of acidity being perfectly compatible with 

 the life of the seminal animalcules ; but Donne has shown 

 that under some circumstances, as from congestion, irritation, 

 or inflammation, this mucus becomes so strongly acid as 

 to destroy in a few seconds the vitality of the spermatozoa. 



Again, the mucus of the uterus in its healthy state is 

 slightly alkaline, but not so much so as to exert any injurious 

 effects upon the spermatozoa ; in conditions of derangement 

 and disease, however, it becomes so alkaline, as Donne has 

 shown *, that in like manner with the acid mucus of the vagina, 

 it kills the seminal animalcules in a very short space of 

 time. 



Now after what has been said and detailed in reference to 

 the essentiality of the spermatozoa, it can scarcely be doubted 

 that women whose vaginal and uterine secretions are so dis- 

 ordered, are inapt to conceive, and this from the effect of 

 their vitiated secretions upon the spermatozoa. 



It would be interesting to determine whether the sperma- 

 tozoa are ever entirely absent from the semen of man : it is 

 very probable that in certain rare cases they are so, and from 

 the facts already ascertained there can be no doubt that 

 those individuals whose spermatic fluid is devoid of its 

 characteristic living element would be wholly incapable of 

 having offspring. 



It is probable, that in the impotent the spermatozoa are 

 almost, if not entirely, extinct. 



* Cours de Microscopic, p. 292. 



