1942 



1 1 1\ MAX ANATOMY. 



2042). The testis is of a whitish color, and, although readily yielding, imparts a 

 characteristic impression of resilience when compressed between the fingers. 



Architecture of the Testis. The framework of the testicle proper consists 

 of a stout capsule, the tunica albuginea, a dense fibro-elastic envelope from .4-. 6 mm. 

 in thickness, that gives form to the organ and protects the subjacent soft glandular 

 tissue. Along the posterior border of the testis the capsule is greatly thickened 

 and projects forward as the mediastinum testis or corpiis Highmori, a wedge-shaped 

 body (from 2.5-3 cm - i n length), from which radiate a number of membranous septa 

 that pass to the inner surface of the tunica albuginea. In this manner the space 

 within the capsule is subdivided into pyramidal compartments, the bases of which lie 

 at the periphery and the apices at the mediastinum. These spaces contain from 150 

 to 200 pyriform masses of glandular tissue, more or less completely separated from 

 one another, that correspond to lobules (lobuli testis). Each of the latter is made up 

 of from one to three greatly convoluted seminiferous tubules, held together by delicate 

 vascular intertubular connective tissue. 



The seminiferous tubules from .15 .25 mm. in diameter and from 25-70 cm. 

 (10-28 in.) in length begin as blind canals, which are moderately branched and 



very tortuous (tubuli contorti} throughout their 

 course until they converge at the apex of the 

 lobule, where they pass over, either directly 

 or after junction with another canal, into the 

 narrow, straight tubules (tubuli recti) that 

 enter the mediastinum and unite into a close 

 net-work, the rete testis. The latter extends 

 almost the entire length of the mediastinum, 

 and consists of a system of irregular inter- 

 communicating channels, the cuboid epithelial 

 lining of which rests directly upon the en- 

 sheathing fibrous tissue of the mediastinum. 

 With these passages the canals of the testicle 

 proper end, the immediate continuation of the 

 spermatic tract being formed by from fifteen 

 to twenty tubules, the ductuli effercntes, that 

 pierce the tunica albuginea along the posterior 

 border and near the upper pole of the testis 

 and, forming the coni vasculosi, connect the 

 sexual gland with the tube of the epididymis. 

 Structure. In contrast to the dense 

 fibro-elastic tissue that composes the f ^ami-- 

 work of the testis, the capsule, mediastinum, and interlobular septa, the con- 

 nective tissue occupying the spaces between the seminiferous tubules is loose in 

 texture and arrangi-im-nt. consisting of delicate bundles of white fibrous tissue in 

 which elastic fibres are few or absent. In addition to the plate-like cells, leucocytes, 

 and eosuiophiles that occur in varying numbers within the meshes of this tissue in 

 conjunction with blood-vessels and nerves, groups or cord-like masses of peculiar 

 polygonal dements, tin- interstitial ceUs, also occupy the intertubular stroma, especi- 

 2 vicinity of the mediastinum. These cells (Fig. 1654), from .015-. 020 

 in diameter, possess relatively small round or oval eccentrically placed nuclei 

 d a finely granular protoplasm that usually contains numerous brownish droplets, 

 t partides, and, sometimes, crystalloid bodies in the form of minute needles 

 In some animals. n,,tably in the hog, the deeply colored interstitial evils 

 orm conspii . tracts that impart a dark tint to the testicle in section. Their sig- 

 s mieertam, but there is reason to regard these cells as concerned in internal 

 set -return, producing a ^.entu- substance. 



I he wall .,t the .-, ,nv, .luted seminiferous tubules consists of a delicate tunica 



mposedd an inner elastic lamella strengthened externally by circularly 



disposed fibres, within uh.rh are several layers of epithelial cells. The latter vary 



only before and after the attainment of sexual maturity, but subsequently with 



fun.n.mal a, m,tv ,-, rest ; in man, however, the variations depending upon these 



FIG. 1651. 



Globus major of epididymis 



Vas deferens 



Coni 



vasculosi 



Ductus 



epidulymidis 



Ductuli 



efferentes 



Tubuli recti 



_Rete testis in 

 mediastinum 

 .Tuhuli 

 contorti 



Vas aberrans 



Ductus 

 epididymidis 

 Globus minor 



Septum Tunica afbuginea 



Diagram showing relations of secretory 

 tubules and system of ducts. 





