432 



THE PENIS. 



The under surface of the united cavernous bodies presents a longi- 

 tudinal groove, in ^vhich is lodged the corpus spongiosum, containing 



Fig. 311. — Root of the Penis attached 

 TO THE Rami op the Pukes and 

 Ischium (from Kobelt). | 



a, a, accelerator urinre muscle covering 

 the bulh of the spongy body of the urethra, 

 ■which presents at e, ijosteriorly, a median 

 notch ; h, b, anterior slips of the muscle, 

 or bulbo-cavernosi ; c, c, crura of the 

 penis, presenting an oval dilatation or 

 bulb of the corpus cavernosum ; d, d, 

 erectores penis muscles ; /, corpus spon- 

 giosum urethrtB. 



the greatest part of the canai of 

 the urethra. The upper or an- 

 terior surface is also marked with 

 a slight median groove in which 

 the dorsal vein of the penis is 

 situated, and near the root is at- 

 tached to the pubes by the sus- 

 l^ensory ligament. 



Structure. — The median sep- 

 tum between the two corpora 

 cavernosa is thick and complete 

 near the root of the penis ; but 

 farther forward it becomes thin- 

 ner, and only imperfectly separates their two cavities, for it presents, 

 particularly towards the anterior extremity, numerous clefts, extending 

 from the dorsal to the urethral edse, and admitting; of a free communi- 



Fig. 312. — Tk.vnsverse Seotion of the Penis in the 

 DISTENDED STATE (altered from Henle). 



The outer line indicates the integument surrounding 

 the deeper parts ; the erectile tissue of the corpora 

 cavernosa and the septum pectiniforme are shown in 

 section ; «, placed on the section of the spongy body, 

 below the urethra ; v, the single dorsal vein ; a, the 

 dorsal artery, and n, the nerve, of one side. 



cation between the erectile tissue of the two 

 sides. From the direction of these slits, the 

 intermediate white portions of the septum 

 resemble somewhat the teeth of a comb, 

 and hence have received the name oi septum pectimforme. 



The external librous investment of the cavernous structure is white 

 and dense, from half a line to a line thick, and very strong and elastic. 

 It is composed for the most part of longitudinal bundles of shining- 

 white fibres, with numerous well-developed elastic fibres, enclosing the 

 two corpora cavernosa in a common covering ; and internal to this, each 

 compartment is surrounded by a layer of circular fibres, which enter 

 into the formation of the septum. 



From the interior of the fibrous envelope, and from the sides of tho 

 BCDtum, numerous lamellae, bands, and cords, composed of fibrous elastic 



