THE ANATOMY OF THE HORSE. 45 



althoujj'h we ot'len liave it broken down in other ways, and in 

 some cases it will disappear of its own accord. The part of the 

 passage in front of the hymen is called the vagina. This passage, 

 in structure, resembles the womb, but is not so strong. There 

 are numerous glands situated along the inner coat or lining of this 

 passage which secrete a fluid to lubricate it. The principal use of 

 this organ is to guide the penis when the animals are performing 

 sexual intercourse, and also serves at the time of foaling as a 

 passage for the foal to come out through The part ot the pas- 

 sage behind the hymen is known as the vulva. It is about four 

 inches long and about two or three inches high, varying according 

 to the size ot the mare. In front it is separated from the 

 vagina by the hymen membrane. It resembles the vagina in 

 structure, and also has little glands in its inner coat to secrete 

 a fluid to lubricate the passage. At the back part of the vulva, 

 or around the outside, is what is known as the lips of the vulva, 

 one on each side of the opening. The outside of the lips are 

 covered by a very fine skin, and, just below the skin, they are 

 made up of erectile tissue, which is the same kind of tissue as is 

 found in the penis of the horse. This tissue is found more 

 abundantly in the lips of the vulva of the young mare than in the 

 lips of the vulva of the old mare. The opening betw^een these lips 

 is situated just below the anus, or the opening where the back 

 bowel ends. At the back part of the vulva, on the under side, is 

 an opening, or hole, about large enough to allow a man's finger 

 to pass in ; this hole is where the tube leading from the bladder 

 comes up into the passage and allows the urine, or water, to pass 

 into the vulva, where it runs out of the body. The clitoris is 

 situated on the under side of this passage, just inside the lips, and 

 can be seen in the mare after passing water when she works the 

 vulva. Just below the clitoris are found two or three small glands 

 which secrete the fluid that passes away when the mare is 

 horsing. 



Mammary Glands, or what is known as the mare's bag, are 

 two gland.s situated between the thighs, the use of which is to 

 secrete the milk after birth to feed the young animal. In 

 the young mare they are very small, but after the mare is 

 with foal a few months these glands begin to get large, and at 

 foaling time they attain their largest size. These glands are 

 coxered out.side by a thin, smooth skin. The substance of tl\em are 



