i8 VETERINARY OBSTETRICS. 



In the Bitch and Cat, the promontory of the 

 sacrum is still more marked than in the Pig, which 

 diminishes notably the inlet of the pelvis; the direction 

 of the symphysis is rectilinear, and the general outline 

 of the cavity is nearly cylindrical, although the inlet is 

 larger below than above. The narrowest part of the 

 canal is immediately above the obturator foramen, 

 where the ischium is wide and shallow, and rises' 

 abruptly to almost a right angle. 



1 ..- 



I - The Vulva. 



This is the most external portion of the female 

 reproductory organs, and presents posteriorly an. 

 opening situated vertically under the rectum, from 

 which organ it is separated by a narrow space — the 

 perineum. 



The labise form the lateral boundaries, and, in the 

 normal condition of the parts, are in contact with eachi 

 other. They are lined on their internal surface withi 

 mucous membrane ; externally with a very smooth skin 

 devoid of hair. 



The cavity of the vulva varies in length in the cow 

 and mare, from six to ten inches. At parturition, the 

 walls become separated to allow of the escape of the 

 foetus. 



The cavity contains several organs accessory ta 

 reproduction, which we will now notice separately. 



Tlie Clitoris. 



This organ is situated on the inferior commissure 

 of the vulva, and corresponds to the corpus cavernosunx 



