INFLUENCE ON SEX CHARACTERS 345 



Now Courrier stated that in the epididymis of the bat a 

 secretory activity also goes on during hibernation. Evidently, 

 as Courrier points out, this exceptional secretory activity 

 during hibernation is rendered necessary on account of the 

 presence of living spermatozoa in the epididymis in this species 

 at a time at which they are absent in other species. The 

 spermatozoa seem to be attracted by the secreting cells. It 

 may be noted that spermatogenesis is at this time suppressed 

 in the testicle, only cells of Sertoli and spermatogonia being 

 present in the seminiferous tubules. On the other hand the 

 interstitial cells are very well developed; they are very active 

 and full of secretory granules. 



It is probable that along the whole passage in the male and 

 female there takes place a secretion of substances which 

 influence the movements of the spermatozoa, and it seems 

 possible that each of these secretions has its specific effect. 

 Various histological observations tend to confirm this. As to 

 the vas deferens the question has been recently studied in a more 

 detailed manner in the mouse by Benoit (1920) in Bouin's 

 laboratory. He records signs of very intense secretory activity 

 in the epithelium of the vas deferens even more pronounced 

 than in the epidid3miis. According to Benoit there is evidently 

 some kind of tropism on the part of the spermatozoa towards 

 the secretion of these cells, the spermatozoa being often found 

 attracted to the secretory masses of the epithelial surface. 



A fine example of secretory activity of the uterine epithelium 

 for maintaining alive the spermatozoa is that afforded by the 

 uterus of the bat. In this animal the spermatozoa are intro- 

 duced into the uterus before the winter begins, whereas 

 ovulation and fecundation take place only in the spring. 

 Courrier (1920 b, 1921) stated that the uterine epithelium 

 assumes its secretory activity just before copulation and the 

 introduction of the seminal fluid, and persists during the whole 

 winter. According to Courrier the spermatozoa are attracted 

 by those cells which are full of secretory granules. He considers 

 the uterine secretion to act in a manner similar to that in the 

 epididymis of the male bat. 



Bottcher (1920) assumes that the secretion of the prostate 

 and of the seminal vesicles may inhibit the noxious influence 

 on the spermatozoa of the acid content of the vagina. Ac- 

 cording to J. Loeb and others (Clowes and Bachman, 192 1) the 



