THE ORGANS OF GENERATION. 83 



The abdominal rings are two on each side, the external and 

 the internal ; the former is the opening in the transverse muscle, 

 the latter in the fascia, or strong membrane, which immediately 

 contains the intestines. They are not placed opposite each other, 

 but about three inches apart, the external ring being situated at 

 the posterior and inferior part of the abdomen. The testicle itself, 

 too, has a coat of peritoneum ; and, when it leaves the abdomen, 

 it forces that portion of the peritoneum which closes the opening 

 with it, and carries it down to the scrotum, thus accounting for 

 two things, — the double membrane of the testicle, and the 

 circumstance of the open communication existing between the 

 scrotum and the abdomen, which, indeed, is the principal cause 

 of the dangerous symptoms which sometimes supervene after the 

 operation of castration. 



The Penis, which serves the double office of affording a pas- 

 sage for the urine, and ejecting the semen, is a long fleshy body, 

 attached to the pelvis by ligaments and muscles. It is composed 

 of several distinct parts, besides its muscles, which are, first, a 

 pair called the erectors, situated at the root of the penis, and at- 

 tached to the bones of the pelvis, which assist in the erection of 

 the organ, by promoting the influx of blood. Then we have a 

 small triangular muscle, situated at the root of the organ, besides 

 the Accelerator, which envelopes the urethra, and ejects with 

 force both the urine and the semen. 



The body of the penis is formed principally of two cavernous 

 bodies, which, by the power they possess of containing a large 

 quantity of blood, increase almost suddenly in size, and thus 

 cause the erection of the penis. 



The extremity of the penis is called the glans, which, in its 

 distended state, is large and rounded, and is the counterpart to 

 the mouth of the uterus in the female, to which it is applied in 

 the act of copulation. At the extremity of the glans is the mem- 

 brane of the urethra, which, in some measure, projects beyond 

 the glans. 



At the commencement of the urethra, near the neck of the 

 bladder, are found three small bodies, called the prostate glands, 

 one of which is much larger than the others. These glands 

 secrete a white fluid, or mucus, which mixes with the semen pre- 

 vious to its ejection. 



The penis of the horse, in its flaccid state, is not usually seen, 

 being altogether situated within its sheath, which is formed by 

 loose folds of skin, reflected on the body of the penis, so as to 

 permit the ready projection or retraction of the organ. 



Within the sheath are situated a number of small glands, 

 which secrete a w^hite odorous substance, which often collects 

 and becomes offensive ; and sometimes insinuates within the ure- 

 thra, and obstructs the passage. 



