SEX. 301 



The physiological objections to this theory, so far 

 as any practical advantages that might be derived 

 from it are concerned, are quite as forcible as the 

 results of direct observation. 



Fecundation, as is well known, is the result of the 

 union of the spermatozoa of the male element with 

 the ovum. Now, this conjunction of the male and 

 the female elements of generation does not take place, 

 in the higher animals at least, at the time of copula- 

 tion, and it is therefore impossible to determine, in 

 any particular case, the precise time that fecundation 

 takes place. Observations upon the lower animals 

 show that the spermatozoa may come in contact with 

 the ovum in the uterus, in the course of the Fallopian 

 tube, or at the ovary. 1 



The precise period at which the ovum escapes 

 from the ovary is uncertain ; some of the best author- 

 ities are of the opinion that the regular time for its 

 escape is toward the termination of the period of heat, 

 while Coste has shown that it may escape in the early 

 part of the period, or toward its close. 3 



The conditions that determine the time of contact 

 of the spermatozoa and the ovum are therefore ex- 

 ceedingly variable, and they may favor an earlier 

 impregnation of the germ in cases of copulation tow- 

 ard the close of the period of heat than would be pro- 

 duced in other cases when copulation took place at 

 the beginning of the period. 



Experiments with dogs and rabbits show that sev- 

 eral days may elapse after copulation before the sper- 



1 Dalton's " Human Physiology," p. 562. 



2 Ibid., p. 661. 



