134 THE STOCK owner's ADVISEE. 



womb, which is thick, round, and projecting in the virgin. In 

 the center is a transverse aperture or fissure opening into the 

 vagina and closed during utero-gestation. The vagina is a mem- 

 branous canal in the center of the pelvis, extending from the 

 uterus to the vulva and situated between the rectum and bladder. 

 It consists of two membranes, an inner mucous and an outer 

 muscular. Constricted at its origin, the vagina widens at its 

 inner portion and surrounds the neck of the uterus. The vagina 

 is the chief female organ of coition. 



The vulva is the external orifice of the urino-genital system, 

 and is situated in the perineal region innnediatelj below the 

 anus. It presents two lips and two commissures. In the interior 

 of the vulva and in a depression on its floor lies the clitoris, 

 which originates by two crura from the ischial arch, and is at- 

 tached to the symphysis by a suspensory ligament. The clitoris 

 is similar in its structure to the penis of the male, and is the 

 principal organ of sexual pleasure in the female; having erectile 

 tissue and cavernous vessels, it becomes erect during copulation. 

 The external orifice of the urethra, the meatus urinaris, opens on 

 the inferior surface of the vulva, about four inches from its 

 opening. It is larger than the male opening and surmounted by 

 a fold of mucous membrane, which acts as a valve. 



The hymen is a thin semilunar fold of mucous membrane 

 which separates the vulva from the vagina, lying immediately 

 before the meatus. It is ruptured during the first act of copu- 

 lation. 



The mammary glands are compound racemose glands, which 

 secrete milk for the nourishment of the recently born animal. 

 They become developed at the age of puberty. The intei'ior of 

 the mamma is composed of lobes divided into still smaller lobules 

 composed of minute ducts and numerous small cells, in which 

 the milk is secreted and conveyed to the ducts, which unite to 

 form a common excretory duct of each. From these ducts pro- 

 ceed the canals that convey the milk to the teat. 



