248 THE PHYSIOLOGY OF REPRODUCTION 



De Bonis ^ describes the epithelial cells of the dog's prostate as 

 containing a small number of granules. When these have been 

 formed in sufficient quantity, so as almost to fill the cell, its wall 

 ruptures and the granules pass out into the lumen of the gland. 

 This occurs especially during coitus. After the discharge of the 

 granules fresh ones are formed in the cells of the gland. 



Little is definitely known regarding the function of the prostate 

 beyond the fact that it contributes additional fluid to the semen. 

 It also appears to cleanse the urethra of urine prior to the 

 ejaculation of semen, since in a stallion (for example) the first fluid 

 to be expelled in sexual intercourse appears to be prostatic fluid and 

 contains no spermatozoa. It may, perhaps, assist in providing the 

 spermatozoa with nutriment.^ There is some evidence, however, 

 that it exercises a stimulating influence upon the movements of the 

 spermatozoa.^ Steinach observed that prostatic fluid, when added to 

 normal saline solution, kept the spermatozoa in active movement for 

 a longer period than saline solution alone. Steinach also found that 

 rats in which the prostate gland, together with the seminal vesicles, 

 was extirpated, were absolutely sterile,* but this may have been due to 

 failure to form a "bouchon vaginal" in the female. As already 

 mentioned (p. 245), the clotting which causes the formation of the 

 " bouchon " in Rodents is believed by Camus and Gley ^ to be due to 

 a ferment (" vesiculase ") which is present in the prostatic fluid.^ 

 The removal of the prostate in Steinach's experiments had no effect 

 in diminishing sexual desire. 



Walker ^ has also adduced experimental evidence pointing to the 

 conclusion that the prostatic fluid of the dog stimulates the sperms 

 to more aetive> movement, 



Iwanoff^ also states that the secretion causes the spermatozoa to 



' De Bonis, "tjber die Sekretionserscheinungen in den Driisenzellen der 

 Prostata," Arch.f. Anat. u. Phys., Anat. Abth., 1907. 



^ It has been suggested also that the prostate is a sphincter of the bladder, 

 but this is rendered unlikely by its absence in the female. 



^ Fiirbringer, toe. cit. KoUiker, " Physiologische Studien liber die Samen- 

 fliissigkeit," Zeitsch. f. wisg. Zool., vol. vii., 1856. 



* Extirpation of the vesiculse seminales alone produced only partial sterility (see 

 p. 246). Walker {Johns Hopkins Hospital Reports, 1911) obtained similar results. 



* Camus and Gley, loc. cit. 



" According to Walker the secretion which causes the clotting is produced 

 by a special gland which he calls the "coagulating gland" {.Johns Hopkins 

 Hospital Bull., vol. xxi., 1910). See below, p, 300. 



' "Walker (G.), " Beitrag zur Kenntniss der Anatomic und Physiologic der 

 Prostata beim Hunde," Arch. f. Anat. u. Phys., Anat. Abth., 1899. 



'* Iwanoff, " Ueber die physiologischen EoUe der accessorischen Geschlechts- 

 drusen, etc.," Arch. f. Mikr. Anat., vol. Ixxvii., 1911. See also Vichnersky 

 {Roussh Vratchi, vol. viii., 1909 ; abstract in Jow. de la Phys. et la Path. Gen.), 

 who found that prostatic secretion obtained by merely squeezing the gland had 

 no effect on sperm movement, but that got by stimulation of nerves caused 

 energetic movement. The properties lasted three days in the cold, but were 

 less marked after boiling. See also Iwanoff, etc., C R. iSoc. Biol, vol. Ixxx. 



