MALE ACCESSORY REPRODUCTIVE ORGANS 239 



especially in the inner or lumen half, but also, though less 

 markedly, in the outer half of each cell (cf. de Bonis' description 

 of the dog's prostate referred to above). 1 



The prostatic secretion is expelled into the urethra during 

 the sexual act by the contraction of the sheath of non-striped 

 muscle which surrounds each tubule throughout its entire length. 



It has been shown in both Man and animals that the growth 

 of the prostate is dependent upon the growth of the testes, since 

 it remains of small size until the time of puberty, when the 

 generative system reaches its full development. In those ab- 

 normal cases in which testicular growth is arrested, the prostate 

 remains in a condition of rudimentary development. Moreover, 

 it has been shown that the prostate in Man normally undergoes 

 atrophy in old age (see p. 676), or as a result of castration, 

 becoming transformed after a few years into a mass of fibrous 

 connective tissue containing a small number of scattered muscle 

 fibres in a state of degeneration. It has been found also that the 

 prostatic tubules disappear almost entirely in castrated animals, 

 and what is left of the epithelium completely loses its secretory 

 function 2 (cf. p. 303). De Bonis' experiments, however, seem to 

 show that the administration of prostatic extract to castrated 

 dogs may lead to a renewal of activity and to the formation of 

 fresh granules in the secretory cells, but this result could not be 

 obtained by employing testicular extract. 



COWPER'S GLANDS 



Cowper's glands are situated near the anterior end of the 

 urethra. They are a pair of small tubulo-racemose glands, and 

 communicate with the urethra by two ducts, apertures of which 



1 See also Griffiths, " Observations on the Anatomy of the Prostate," 

 Jour, of Anat. and Phye., vol. xxiii., 1889. For the comparative anatomy 

 of the prostate, see Oudemans' Die Acceasorischen Oeschlechtsdrusen der 

 Stiugethiere, Haarlem, 1892. According to this authority, the hedgehog has 

 two pairs of prostates. The homologies of these glands in Insectivores 

 still seem to he obscure. See below, under Cowper's glands. 



2 Griffiths, toe. cit. Cf. also Griffiths, " The Condition of the Testes and 

 Prostate Gland in Eunuchoid Persons," Jour, of Anat. and Phya., vol. xxviii., 

 1893 ; Walker (G.)," Experimental Injection of Testicular Fluid to prevent the 

 Atrophy of the Prostate Gland after the Removal of the Testes," Johns Hopkins 

 Hospital Bull., vol. xi., 1900; Wallace (Cuthbert), "Prostatic Enlarge- 

 ment," London, 1907 ; de Bonis, toe. cit. 



