THE UBOGENTTAL SYSTEM 147 



urethra. They secrete fluids which are poured into the latter 

 tube for the purpose of f acihtating the passage of the testicular 

 secretion. They also dilute the secretion from the testicles, 

 adding volume to it so that it is more likely to reach the ovum. 



The penis is largely composed of erectile tissue — the corpus 

 cavernosum. The organ extends from the ischial arch, where 

 it is firmly attached, forward between the thighs. It has at the 

 free end a covering of skin, called the prepuce or sheath (Fig. 49). 

 The inner layers of the prepuce are supplied with large sebaceous 

 glands; the secretion is named smegma. The latter has a tend- 

 ency to collect in the horse and cause "foul sheath " unless washed 

 out at intervals. When the diverticulum of the fossa of the glans 

 penis becomes filled with smegma, it causes the formation of a 

 "bean," which sometimes materially interferes with urination. 

 The bull's penis has an S-shaped curve (Fig. 48). The penis is 

 the male copulatory organ. 



The urethra of the stallion and bull is the long mucous tube 

 which extends from the bladder to the lower or anterior end of 

 the penis. It passes backward on the floor of the pelvis, turns 

 around the ischial arch, and then runs forward and downward, 

 embedded in the spongy tissue of the penis. The urethra con- 

 veys the urine and the semen. 



THE REPRODUCTIVE ORGANS OF THE FEMALE 



The female genital organs are the ovaries, the fallopian tubes, 

 the uterus, the vagina, the vulva, and the mammary glands (Fig. 

 50). 



The ovaries are two in number, and much smaller than the 

 testicles, with which they are homologous. They are situated 

 about a hand breadth behind the corresponding kidney. A fold 

 of peritoneum attaches them loosely to the sublumbar region. 

 Embedded in the fibrous tissue of the substance of the ovary 

 are little masses of epithelial cells from which the graafian follicles 

 and eventually the ova develop. The functional value of the 

 ovaries is to form the ovum or female reproductive cell. 



The fallopian tubes are two tortuous passages, about 10 inches 

 long and about ~% of an inch in diameter, that run between the 

 layers of the broad ligaments. The ovarian end of the tube is 

 fringed or fimbriated, and expanded into a funnel-like infun- 



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