GENERAL ANATOMY OF ERECTILE TISSUE. 181 



eter, and are of the same size whether they are derived from 

 the larger branches or the finest twigs. 



The arteriae helicina3, sometimes branch off singly ; sometimes 

 in little bundles from three to ten in number, in which/ case 

 they originate by a common trunk. They project constantly 

 into the cells of the spongy substance, which Miiller considers 

 venous cavities, and either terminate abruptly, or swell out 

 into a club-like process without again subdividing. These 

 vessels when they project into the venous cavities, according to 

 Miiller, are not entirely naked, but are covered by a delicate 

 membrane, which, under the microscope, appears granular, 

 and when the arteries form a bundle like a skein of thread, the 

 whole bundle is covered by a gauze-like membrane. Miiller 

 considers this membrane as performing an important part 

 in the phenomena of erection. The arteries have neither 

 on their sides or extremities, any openings discoverable 

 with the microscope ; and when the blood, as is probable, 

 escapes from them in large quantities into the venous cells 

 during erection, it must either pass through invisible open- 

 ings or by orifices which become enlarged by the dilatation of 

 the arteries. These helicine arteries appear to have been seen 

 by Weber, and figured in his plates, though not under that par- 

 ticular name, (Vide Tab. xxvi. figs, xxvii. xxviii.)* 

 The discovery of these vessels by Miiller, though they do 

 not by any means fully explain to us the phenomena of erec- 

 tibility, goes far towards reconciling the two conflicting opinions 

 entertained upon this subject. That the cells formed by the 

 septae of the corpus cavernosum and spongiosum penis, are 

 lined with the lining membrane and continuous with the cavity 

 of the veins, there can, I think, be little doubt. For with the 

 injecting pipe plunged at random in the cells of these parts, we 

 invariably succeed in filling the superficial veins of the penis ; 

 and by inserting a pipe in the vena magna ipsius penis, we 

 are equally successful in distending with injecting matter, 

 the spongy cells. In these cells ramify the helicine arteries of 



* Mailer's Archives, or London Medical Gazette, No. 423. 

 VOL. II. 16 



