FECUNDATION. 34:3 



In both of these, he found ova at the superior extremity of 

 the cornua of the uterus, a position which he had found that 

 the ova reached toward the end of the third day. These ova, 

 which were apparently advanced in decomposition, present- 

 ed no evidence of fecundation, and were enveloped in a dense 

 zone of albumen which they had received from the Fallopian 

 tubes. They were surrounded by spermatozoids in active 

 movement, but none had penetrated the adventitious albu- 

 minous covering. From these observations, the conclusion is 

 deduced that fecundation can only take place at the ovary or 

 in the most dilated portion of the Fallopian tubes. 1 When 

 we come to apply these observations to the human subject, 

 we have, in confirmation of them, only the abnormal phe- 

 nomenon of abdominal pregnancy, which cannot occur unless 

 the ovum have been fecundated at the ovary, afterward falling 

 into the abdominal cavity instead of passing to the uterus. 

 Still, the fact that conception may follow a single intercourse 

 occurring at any time with reference to the menstrual period 

 throws a doubt upon the theory that fecundation takes place 

 only at or near the ovary ; and another element of uncer- 

 tainty is in the fact that we do not know positively that 

 ovulation takes place at any definite time before, during, or 

 after the menstrual period, nor do we know precisely how 

 long the spermatozoids may retain their vitality in the female 

 generative passages. 



The question of the duration of vitality of the spermato- 

 zoids after their passage into the uterus has an important 

 bearing upon the time when conception is most liable to fol- 

 low sexual intercourse. The alkaline mucus of the internal 

 organs actually favors their movements ; the movements are 

 not arrested by contact with menstrual blood; and, indeed, 

 when the spermatozoids are mixed with the uterine mucus, 

 they simply change their medium, and there is no reason to 

 believe that they may not retain their vitality as well as 

 in the mucus of the vesiculse seminales. "We cannot, there- 



1 COSTE, Developpemcnt dcs corps organises, Paris, 1859, tome ii., p. 79, et seq. 



