402 



HISTORY OF THE HUMAN BODY 



such elementary structures are derived the two other sets, the 

 prostate and the bulbo-urethral [Cowper's]. Of these the 

 former are more proximal in position, the latter more distal. 

 The function of these five sets of glands seems in all cases 

 that given above, and their occurrence in the various mam- 



FIG. 113. Penis of placental mammals. 



(A) Mouse (.Mus musculus). [Combined from RAUTHER and OPPEL.] (B) 

 Hedgehog (.Erinaceus curopaeus.) [From OPPEL, after SEUBERT.] 



k, kidney; u, ureter; b, bladder; t, testis; e, epididymis; v. d., ductus deferens; 

 cc, corpora cavernosa; v, vesicular glands; pr, prostate glands; c, bulbo-urethral 

 (Cowper's) glands; p, preputial glands. 



mals is such that the large development of one is compensatory 

 for the small size of another. 



Thus in monotremes and marsupials there is no prostate 

 gland, but the urethral glands are very abundant ; the vesicular 

 glands are wanting in carnivores, but large and well developed 

 in primates. In Man the most important of these is the pros- 

 tate, but the vesicular are also well developed. The bulbo- 

 urethral glands are evident but not voluminous. In addition 



