122 



PHYSIOLOGY 



CHAP. 



radiate fanwise many chin fibrous laminae or septa which are 

 continued to and reunite at the internal face of the tunica 

 albuginea so as to form pyramidal spaces containing the soft, 

 yellowish-brown substance of the parenchyma, which in this way 

 becomes divided into a great number of lobules (250-300 according 

 to Sappey). 



The parenchyma of the lobules is formed of a mass of fine, 

 convoluted seminiferous tubules bound together by an interstitial 

 substance. At the apex of each lobule the tubules become 



Lobule 



Tunica albuginea 



-Head of epididymis 



- Retetestis 



Body of epididymis 



Mediastinum 

 Vas defercns 

 PIG. 17. Sagittal section of the testicle and epididymis. (Bohm and Davidoff.) 



straight, penetrate the mediastinum, and unite, forming the rete 

 testis, from which emerge the efferent ducts which pass into the 

 head of the epididymis, and after a complicated course open into 

 a single canal called the vas defer ens (Fig. 19). The convoluted 

 seminiferous tubules have a diameter of 0'15-0'18 mm. (Sappey), 

 and to the number of 3 or 4 or even 5 or 6 are found in each 

 lobule. With suitable methods of maceration and separation they 

 can be isolated and unfolded in order to estimate their length, 

 which proves to be 30-35 cm. in the smaller lobules, and 120-175 

 in the larger. The different tubules of each lobe unite in one 

 straight tubule before forming the rete testis. 



Each convoluted tubule is covered by a delicate homogeneous 



