INFLUENCE ON SEX CHARACTERS 343 



avoided in such an operation as prostatectomy. Further, 

 Lichtenstern showed that spermatogenesis proceeded quite 

 normally in his rats from which the prostate was completely 

 removed at an early age. These observations are opposed to 

 the conclusion of Serralach and Pares, especially as in the 

 experiments of the latter it is probable that there was never a 

 complete removal of the prostate, this operation being almost 

 impossible in the adult animal. 



The interstitial tissue of the testicle in animals prostatec- 

 tomized at an early age was found by Lichtenstern to be also 

 quite normal. 



C. THE SECRETION OF THE GENITAL PASSAGES 



IN RELATION TO THE VITALITY OF 



THE SPERMATOZOA. 



It was stated above that, although the seminal vesicles and 

 the prostate have no influence on the somatic sex characters 

 and on the psycho-sexual behaviour, they are nevertheless 

 necessary for normal fertility. As we have learned that sper- 

 matogenesis also is independent of the seminal vesicles and 

 the prostate gland, it seems likely that decrease or absence 

 of fertility after removal of the seminal vesicles and the prostate 

 is due to a change in the vitality of the spermatozoa. We have 

 already touched upon this question above. 



The question as to the influence of the secretion of the male 

 accessory glands on the spermatozoa is a very old one. Kolliker 

 stated that the secretion of the uterus masculinus of the rabbit 

 and that of the seminal vesicles of man has the power of 

 stimulating the movements of spermatozoa, these becoming 

 quicker and lasting longer. Similar statements have been 

 made by Fiirbringer about the secretion of the prostate. 

 Steinach studied the influence of the secretion of the seminal 

 vesicles and of the prostate on the spermatozoa of the rabbit, 

 guinea pig, mouse and rat. He found that in the secretion of 

 the prostate the movements of spermatozoa last longer than 

 in a physiological salt solution. The most effective fluid, 

 according to Steinach, is a solution of the prostatic secretion 

 with a few drops of physiological salt solution. According to 

 Hirokava the alkalinity of the prostatic secretion is of a special 

 importance for the vitality of the spermatozoa ; it was already 



