880 GENERATION. 



two testicles, with their coverings, vessels, nerves, etc. The skin of the scrotum encloses 

 both testicles, but is marked by a median raphe. Immediately beneath the skin, is a 

 loose, reddish, contractile tissue, called the dartos, which forms two distinct sacs, one 

 enveloping each testicle, the inner portion of these sacs fusing in the median line, to form 

 the septum. Within these two sacs, the coverings of each testicle are distinct. These 

 organs are, as it were, suspended in the scrotum by the spermatic cords, the left usually 

 hanging a little lower than the right. The coverings for each testicle, in addition to 

 those just mentioned, are the intercolumnar fascia, the cremaster muscle, the infundi- 

 buliform fascia, the tunica vaginalis, and the proper fibrous coat. 



The tunica vaginalis is a shut sac of serous membrane, covering the testicle and epi- 

 didymis, and reflected from the posterior border of the testicle to the wall of the scrotum, 

 lining the cavity occupied by the testicle on either side, and also extending over the 

 spermatic cord. This tunic is really a process of peritoneum, which has become shut off 

 from the general lining of the abdominal cavity. The spermatic cord is composed of 

 the vas deferens, blood-vessels, lymphatics, and nerves, with the various coverings already 

 described, which expand and surround the testicle. 



Beneath the tunica vaginalis, are the testicles, with their proper fibrous coat. These 

 organs are ovoid, and flattened laterally and posteriorly. " They are from an inch and 

 a half to two inches long, about an inch and a quarter from the anterior to the posterior 

 border, and nearly an inch from side to side. The weight of each varies from three- 

 quarters of an ounce to an ounce, and the left is often a little the larger of the two." 

 (Quain.) The proper fibrous coat is everywhere covered by the closely adherent tunica 

 vaginalis, except at the posterior border, where the vessels enter and the duct passes 

 out. At the outer edge of this border, is the epididymis, formed of convoluted tubes, pre- 

 senting a superior enlargement, called the globus major, a long mass running the length 

 of the testicle, called the body, and a smaller enlargement inferiorly, called the globus 

 minor. This, too, is covered with the tunica vaginalis. Between the membrane cover- 

 ing the testicle and epididymis and the layer lining the scrotal cavity, is a small quan- 

 tity of serum, just enough to moisten the serous surfaces. At the superior portion 

 of the testicle, we usually find one or more small, ovoid bodies, each attached to the 

 testicle by short, constricted processes, which are called the hydatids of Morgagni. 

 These have no physiological importance and are supposed to be the remains of foetal 

 structures. 



The proper fibrous coat of the testicle is called the tunica albuginea. It is white, 

 dense, inelastic, measures about -fa of an inch in thickness, and is simply for the protec- 

 tion of the contained structures. Sections of the testicle, made in various directions, 

 show an imcomplete vertical process of the tunica albuginea, called the corpus Highmo- 

 rianum, or the mediastinum testis. This is wedge-shaped, about | of an inch wide at 

 its superior and thickest portion, is pierced by numerous openings, and lodges blood- 

 vessels and seminiferous tubes. From the mediastinum, numerous delicate, radiating 

 processes of connective tissue pass to the inner surface of the tunica albuginea, dividing 

 the substance of the testicle into imperfect lobules, which lodge the seminiferous tubes. 

 The number of these lobules has been estimated at from one hundred and fifty to two 

 hundred. Their shape is pyramidal, the larger extremities presenting toward the sur- 

 face, and the pointed extremities situated at the mediastinum. 



Lining the tunica albuginea and following the mediastinum and the processes which 

 penetrate the testicle, is a tunic, composed of blood-vessels and delicate connective tissue, 

 called the tunica vasculosa, or pia mater testis. 



Lodged in the cavities formed by the trabeculse of connective tissue, are the semi- 

 niferous tubes, in which the male elements of generation are developed. These tubes 

 exist to the number of about eight hundred and forty in each testicle and constitute 

 almost the entire substance of the lobules. The larger lobules contain five or six tubes, 

 the lobules of medium size, three or four, and the smallest frequently enclose but a single 



