STRUCTURE OF THE PENIS. 315 



The erectile plexus of the corpora cavernosa penis is on this 

 account, according to Langer, to be regarded as " a spacious 

 rete mirabile, which, in regard to the vena dorsalis, is unipolar ; 

 but in regard to the venae profundse, is bipolar." 



The same author distinguishes an external and an internal 

 part in the corpus cavernosum urethrse. The external consists of 

 a dense plexus of veins, forming the rete mirabile venosum of 

 Kohlrausch and Jarjavay, and constituting the proper erectile 

 body of the urethra. The inner part is the venous plexus of 

 the urethra itself, and is composed of smaller longitudinal 

 and perfectly parallel vessels that communicate by means of 

 numerous short and tortuous anastomoses. The outer part is 

 continued uninterruptedly into the bulb as an erectile plexus, 

 whilst the inner is continued through the pars membranacea 

 and prostatica to the bladder in the form of a submucous venous 

 plexus. 



The arteries give off some branches to the mucous membrane 

 of the urethra, where they break up into capillaries, whilst 

 others remain in the corpus cavernosum, and then divide into 

 their capillary branches. 



The circulation in the corpus cavernosum urethrae is every- 

 where accomplished by means of capillaries. The roots of the 

 venous efferent canals the venae efferentes arise from smaller 

 vessels coalescing to form single trunks. 



The vascular system of the glans presents similar characters. 



The cavernous tissue here also is a rete mirabile venosum, 

 arising from capillaries (Hausmann, Kobelt, Jarjavay). The 

 coarse venous plexus, as we have already stated, is traversed 

 by a close fine plexus ; numerous loops from the most super- 

 ficial capillary plexus ascend into the papilla of the glans, 

 just as from the cavernous spaces of this body. The 

 branches of these loops are characterized by their tortuous 

 course (Langer), and indeed many of them are distinctly 

 coiled. 



The connection of the erectile body of the glans with that 

 of the urethra is effected by the venae efferentes glandis, the 

 finer branches of this convoluted mass of veins lying in the 

 glans, the coarser in the corpus cavernosum urethrae. 



This convoluted mass of veins lies on the dorsal' surface of 



