The Vagina 31 



-with the anterior parietal attachment of the ligament much 

 farther forward, renders the accident comparatively rare. 



The comparative amplitude of the ligament in the cow, with 

 its most anterior point of parietal attachment but little forward 

 •of the pelvis, permits more readily of inversion and prolapse of 

 the uterus and vagina (which see) than obtains in other animals. 



In muciparous animals the broad ligaments are necessarily 

 -very extensive and uniformly have their anterior point of attach- 

 ment to the abdominal walls far forward in the post-renal 

 Tegion. In the bitch, the ligament at its anterior border is very 

 short so that the ovary and ovarian end of the cornu is closely 

 fixed in the sublumbar region just posterior to the kidney and 

 tends to stretch the cornu between this anterior, sublumbar at- 

 tachment and the vagina. 



The ligament being exceedingly ample except at the anterior 

 horder, it is much longer than the distance from its parietal 

 attachments to the position of the cornu, resulting in a large 

 antero-posterior fold which drops down on the median side of 

 the cornu and covers it in this double fold of broad ligament. 



<Fig- 3). 



Unlike in other domesticated animals, the broad ligaments of 

 the bitch are uniformly the seat of extensive deposits of fat, 

 -which causes them to strongly resemble the gastric omentum in 

 general appearance. 



5. The Vagina. 



The vagina is a musculo-membranous canal, formed from the 

 fusion of the posterior ends of Mueller's ducts and extending 

 from the uterus to the vulva. Limited anteriorly by the os uteri 

 externum, it ends posteriorly at the position of the hymen, just 

 anterior to the meatus urinarius, where the vulva succeeds it. 



In the mare it is 8 to 12 inches in length and capable of lateral 

 distension to the full size of the pelvic cavity. Lined with 

 squamous epithelium, its mucosa is thrown into longitudinal 

 folds, which, when at rest, lie in contact with each other. 



The mucous membrane of the vagina has in its deeper portions 

 numerous mucous glands which serve to keep the surfaces at all 

 times moist and which become especially active during sexual 

 -excitement and at the close of pregnancy. The muscular coat 

 •does not differ fundamentally in arrangement from that of the 

 uterus though less in volume. 



