2/8 HISTOLOGY. 



vascular nets, form a thick plexus myospermaticus provided with sym- 

 pathetic ganglia. It is found in the muscular layer and occurs more highly 

 developed in the ductus deferens and seminal vesicles. Its fibers supply 

 chiefly the smooth muscles, and to a less extent, the mucosa. 



DUCTUS DEFERENS. 



The ductus deferens begins as a convoluted tube continuous with 

 the ductus epididymidis; it becomes straight and passes to its termina- 

 tion in the ductus ejaculatorius. Shortly before reaching the prostrate 

 it exhibits a spindle shaped enlargement, about in. long and f in. 

 wide, known as the ampulla (Fig. 317). The ductus deferens consists of a 



tunica mucosa, muscu- 

 laris and adventitia. 



:^ Epithet, The epithelium is gen- 



- v :- ; erally in two rows, the 



tall inner cells producing 



.- Tunica propria. 



round masses of secre- 

 inner longitu- tion. Toward the epi- 



. j.': dinal muscles. 



^HJglt-- didymis it may also have 



f %LW~ -muscles. non-motile cilia. To- 



ward the ampulla it may 

 r ;, V. be several rowed, resem- 



V {' )uter longitu- -IT r 



' dinai muscles. blmg the epithelium of 

 the bladder. It rests on 



T*..-' --__ Connective 



. a connective tissue tunica 



propria which is sur- 

 rounded by the three 



FIG. 316. CROSS SECTION" OF THE HUMAN DUCTUS " 



x 24 - layers of the muscularis. 



The inner and outer 



layers are longitudinal and generally less developed than the middle cir- 

 cular layer. The adventitia is a loose elastic connective tissue, blending 

 with that of the spermatic cord which contains numerous arteries, veins, 

 lymphatics, nerves, striated muscle fibers of the cremaster muscle, and 

 the rudiment of the processus vaginalis. 



In the ampulla the longitudinal folds which are low in the ductus 

 deferens, become tall and branched so that they partly enclose irregular 

 spaces (diverticula). Similar folds occur in the seminal vesicles. It is 

 doubtful whether in either place any of them should be considered glands. 

 Around the ampulla the musculature is irregularly arranged; the longi- 

 tudinal layers separate into strands which terminate toward the ejacu- 

 latory ducts. 



