360 THE GENITOURINARY ORGANS. 



The epithelium of the vestibulum gradually assumes the char- 

 acteristics of the epidermis ; its outer cells lose their nuclei and 

 sebaceous glands occur here and there in the neighborhood of the 

 urethral orifice and on the labia minora. Hair begins to appear on 

 the outer surface of the labia majora. 



The clitoris is covered by a thin epithelial layer, resembling the 

 epidermis. This rests on a fibrous-tissue mucosa having numerous 

 papillae, some of which contain capillaries, others special nerve- 

 endings. In the clitoris of the adult no glands are found. The 

 greater portion of the clitoris consists of cavernous tissue, homol- 

 ogous to the corpora cavernosa of the penis ; the corpus spongi- 

 osum is not present in the clitoris. 



The glands of Bartholin, the homologues of the gla'nds of 

 Cowper in the male, are mucous glands situated in the lateral 

 walls of the vestibule of the vagina. The terminal portions of 

 their ducts are lined by stratified squamous epithelium. 



Free sensory nerve-endings, with or without terminal enlarge- 

 ments, have been demonstrated in the epithelium of the vagina 

 (Gawronski). The sensory nerve-fibers form plexuses in the 

 mucosa, and lose their medullary sheaths as they approach the 

 epithelium. Sympathetic ganglia are met with along the course of 

 these nerves, and nonmedullated nerves terminate in the involuntary 

 muscular tissue of the vaginal wall. 



In*the connective-tissue papillae and in the deeper portions of the 

 mucosa of the glans clitoridis are found, besides the ordinary type 

 of tactile corpuscles and the spherical end-bulbs of Krause, the so- 

 called genital corpuscles (see p. 171). Numerous Pacinian cor- 

 puscles have been observed in close proximity to the nerve-fibers 

 of the clitoris and the labia minora. 



In varying regions of the medullary substance of the ovary, 

 but more usually in the neighborhood of the hilum, there occur 

 irregular epithelial cords or tubules provided with columnar epithe- 

 lium, ciliated or nonciliated, which constitute the paroophoron. 

 These are the remains of the mesonephros, and are continuations 

 of that rudimentary organ the epoophoron of similar structure 

 which lies within the broad ligament. The separate tubules of the 

 epoophoron communicate with the duct of Gartner (Wolffian duct), 

 which in the human being is short, ends blindly, and never, as in 

 certain animals, opens into the lower portion of the vagina. These 

 derivatives of the primitive kidney consist of blindly ending tubules 

 of varying length lined by a ciliated epithelium, the cells of which 

 are often found in process of degeneration. 



The hydatids of Morgagni are duplications of the peritoneum. 



