228 OBSTETRICS. 



the peritoneum which extend the whole length of the body and 

 horns, one on each side. They attach in the sub-lumbar region 

 above, and to the sides of the uterus below. A third ligament at- 

 taches above to the rectum, and a fourth below to the floor of the 

 pelvis. 



Openings. — Three: one behind into the vagina; two in front 

 for the Fallopian tubes. 



Function. — The function of the uterus is to receive and ma- 

 ture the ovum after it has been fertilized. The ovum attaches 

 to the uterine wall; a covering and supporting membrane is de- 

 veloped around it ; and there the foetus develops, receiving a rich 

 supply of oxygen and food materials from the maternal uterine 

 walls, through the surrounding membranes by osmosis. 



FIG. 81. GENERATIVE ORGANS OF THE MARE. 



1, Ovaries; 2, Fallopian lubes; 6, hoiii ,,( uteius iiitaet; 7, horn of uterus 

 laid open; 8, ifody of uteru.s; 9, broad ligament; 10, cervix or neck ot tne 

 uterus; 13, outlet of the urethra. 



Vagina. — This is a membranous tube which contains much 

 muscular tissue in its walls. 



Structure. — Three coats, (a) outer of loose connective tissue; 

 (b) middle, muscular; (c) inner, mucous. 



Location. — Tn the pelvis between the rectum above and the 

 floor of the pelvis below. It is capable of great dilation to allow 

 the passage of the young at birth. Between the uterus and. vagina 

 the connection or common opening is through the neck, at which 

 point the uterus narrows greatly and is composed of firmer tissue. 

 As the time for delivery approaches, this narrow canal dilates until 

 the opening is large enough for the young animal to pass through. 



