228 



THE UROGENITAL' SYSTEM 



The bulbo-urethral glands (of Cowper) arise in male embryos of 30 mm. 

 (C R) as solid, paired epithelial buds from the entoderm of the urogenital sinus. 

 The buds penetrate through the mesenchyme which forms the corpus cavernosum 

 urethrse, about which they enlarge. The glands branch, and, at 120 mm. (C R), 

 the epitheUum becomes glandular. The vestibular glands (of Bartholin) are the 

 homologues in the female of the bulbo-urethral glands. They appear in em- 

 bryos of 30 mm. (C R), grow until after puberty, and degenerate after the 

 cUmacterium. 



HOMOLOGIES OF INTERNAL AND EXTERNAL GENITALIA 



Hermaphroditism. — True hermaphroditism consists in the development and 

 persistence of both testes and ovaries in the same individual. It is of rare oc- 

 currence in man (according to Pick, Arch. f. mikr. Anat., Bd. 84, 1914, four 

 authentic cases only), is not uncommon in the lower vertebrates, and is the 

 normal condition in many invertebrates (earth worms, snails, etc.). In cases of 

 human hermaphroditism of this type the secondary sexual characters are usually 

 intermediate between the male and female, tending now one way, now the other. 

 The external genitaha show a small penis with hypospadias, cryptorchism, or 

 small vaginal opening. 



False hermaphroditism is characterized by the presence of genital glands of 

 one sex in an individual which exhibits more or less marked secondary characters 

 and external genitaha of the opposite sex. In mascuhne hermaphroditism an in- 



