stance called the epididymis. This canal, formed by the union of the 

 ducts of the corpus Highmorianum, at first convoluted on itself, becomes 

 less and less tortuous, as it approaches the lower extremity of the testi- 

 cle : there it bends back and ascends under the name of vas deferens, 

 along the spermatic cord, as far as the inguinal ring, by which it enters 

 the abdominal cavity. The vasa deferentia, though of the size of a quill, 

 have, nevertheless, a very small cavity, and it is not easy to say why a 

 capillary tube should have such thick pareties, and nearly as hard as 

 cartilage. 



The semen, secreted by the testicles, is formed from the blood conveyed 

 to them by the spermatic arteries, long, slender, and very tortuous ves- 

 sels, arising from the aorta, at a very acute angle. This fluid is filtered 

 through the seminiferous tubes, passes into those of the corpus High- 

 morianum, and thence into the vasa deferentia, which, after they have en- 

 tered the abdomen, terminate into the vesicuse seminales, and deposit into 

 them the spermatic fluid. The delicacy of the organization of the testicle, 

 the delicacy of the vessels along which the semen is conveyed, account 

 for its tendency to congestion, and for the difficulty with which a resolu- 

 tion of this affection is obtained. 



The spermatic fluid passes, from the vasa deferentia, into the vesicular 

 seminales, notwithstanding the retrograde direction of their course. The 

 cavities serving as receptacles to the semen, resemble, in this respect, the 

 gall bladder. Notwithstanding the unfavourable direction in which the 

 ducts of the liver and of the testicles join in their respective receptacles, 

 they nevertheless convey the fluids into the latter ; the bile, because the 

 ductus choledocus is pressed by the coats of the duodenum, contracted 

 on itself when empty 5 the semen, because the duct along which it is con- 

 veyed, penetrating through the prostate gland, and opening into the ure- 

 thra, by a very narrow orifice, this fluid flows back more readily into the 

 vesiculae seminales, than from the vas deferens into the ejaculatory duct. 



The vesiculae seminales form two membranous receptacles of different 

 capacity, in different individuals, larger in young people and adults, than 

 in children and old people. Their cavity is divided into a number of 

 cells ; they are lined with a mucous membrane, which secretes, in con- 

 siderable quantity, a viscid humour that mingles with the semen, in- 

 creases its quantity and serves as a vehicle to it. The situation of the 

 vesiculae seminales, between the rectum, the levatores ani, and the pos- 

 terior part of the bladder, promotes the excretion of their contents, 

 (which is chiefly brought about by the contraction of their parietes) by the 

 compression of the levatores ani, which are in a state of convulsion at the 

 moment of emission. Animals that are not provided with these seminal 

 receptacles, remain a considerable time in a state of copulation, the pro- 

 lific fluid necesfary to impregnation having to be secreted during the 

 time that the copulation lasts, and flowing in drops. 



The ducts formed by the union of the vesiculae seminales with the vasa 

 deferentia, pass through the prostate gland, and open, by separate ori- 

 fices, into the urethra, at the bottom of a lacuna, near the verumoritanum. 

 The glandular body in which they are inclosed, and which contains both 

 the neck of the bladder and the beginning of the urethra, does not exist 

 n women. The mucous and whitish fluid, secreted by the prostate, is 

 conveyed by ten or twelve orifices into the urethra. This prostatic fluid 

 mingles with the semen, adds to its quantity, is perhaps emitted first, in 

 order to lubricate the internal surface of the canal, and prepare it for the 



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