THE ABDOMEN 633 



inferior layer of the triangular ligament. In front of the bulbs 

 there is a plexus of veins which is continuous behind with their 

 erectile tissue, and in front with that of the glans clitoridis. This 

 plexus of veins is kno\sTi as the pars intermedia of Kobelt. It 

 receives its veins from the labia minora, and its blood is conveyed 

 into the vaginal plexus. 



The bulbi vestibuU, together, represent the bulb of the male 

 urethra, which latter presents on its imder surface a faint groove in 

 the middle line, indicating a tendency to a bipartite division. The 

 pars intermedia of Kobelt is regarded as representing that part of 

 the male corpus spongiosum which extends from the bulb to the 

 glans penis. 



The glands of Bartholin or of Duvemey belong to the class of 

 racemose or acino-tubular glands. They are two in number, right 

 and left, and each resembles a small bean. They lie on either side 

 of the external orifice of the vagina towards its back part, immedi- 

 ately behind the posterior extremities of the bulbi vestibuli, and 

 superficial to the base of the triangular ligament. The duct of each 

 gland is about | inch long, and opens in the angle between the 

 attached border of the njonpha posteriorly and the hymen or its 

 remains, close to the centre of the margin of the vaginal orifice. 



These glands are homologous with the glands of Cowper, and their 

 structure is similar. 



The glands of Bartholin are developed iiova the lining epithelium of the 

 uro-genital sinus. 



The external uro-genital organs of the female have received the 

 name of vulva. As this word, however, literally signifies ' a 

 covering,' it is strictly applicable only to the labia majora, which by 

 their approximation form a covering for the uro-genital space and 

 its contents. 



Development of the External Genital Organs. 



In the early stages no sexual differences are apparent in the de- 

 velopment of the external genital organs. The chief parts concerned 

 are — (i) the genital eminence, (2) the genital groove, (3) the internal 

 genital folds, and (4) the external genital folds. 



Female External Organs. — ^The surface-depression corresponding to 

 the cloacal membrane, which bounds the cloaca postero-inferiorly, 

 is known as the cloacal depression. As the cloaca becomes divided 

 into two compartments — dorsal or intestinal, and ventral or uro- 

 genital — ^by the cloacal or uro-rectal septmn, the cloacal membrane 

 is also divided into two parts — dorsal or anal, and ventral or uro- 

 genital. Moreover, the superficial cloacal depression is likewise 

 divided into two parts — dorsal, which is called the anal depression 

 or proctodeum ; and ventral, which is known as the uro-genital 

 depression, and is somewhat cleft-like. When the uro-genital 

 portion of the cloacal membrane ruptures the uro-genital sinus or 

 canal communicates with the exterior by means of the uro-genital 

 opening or cleft. 



