OF THE ERECTILE TISSUE. 271 



urethra, the nymphro, the nipple, the papillcc of the tcgumen- 

 tary membranes, &c. 



399. The erectile tissue is of very large dimensions in the 

 organs of copulation. Though it does not present the same de- 

 velopment in the papillae, yet it may be very distinctly ob- 

 served in them. 



The papillae, those of the tongue in particular, consist of en- 

 larged soft nervous filaments, destitute of neurilema, inter- 

 mingled with an innumerable multitude of capillary blood- 

 vessels, tortuous, arched, and anastomosing with each other, 

 the whole enveloped and collected together by a soft and mu- 

 cous cellular tissue. In a state of rest these papillae are small, 

 soft, pale, and indistinct. In that of erection, on the contrary, 

 they are enlarged, raised up, of a red colour, swollen with 

 blood, and possessed of great sensibility. 



The nipple or the papilla of the mamma3, appears to differ 

 from the others only in being of larger dimensions. The skin 

 and mucous membrane present the papillary and erectile dis- 

 positions in various degrees, in their whole extent. The 

 volume of the nerves and the quantity of the blood-vessels, 

 are every where proportionate to the degree of sensibility. 

 The skin of the pulp of the fingers, which is very vascular and 

 nervous, experiences a degree of swelling, and of manifest red- 

 ness during the act of touching, proportionate to its perfection. 

 400. The erectile tissue of the organs of copulation differs 

 from that of the papillae only in having its dimensions much 

 larger. That of the corpus cavernosum of the penis presents 

 the following disposition. It is enveloped by a sheath of elas- 

 tic fibrous tissue, which sends prolongations into its interior. 

 The two dorsal arteries of the penis are accompanied by an 

 azygos vein forming a plexus, and by nerves of great size. 

 The arteries send into the interior numerous minute branches 

 accompanied by nerves, and the veins receive numerous radi- 

 cles through the sheath. The interior is composed of arterial 

 ramifications coming from the doral arteries, and central ar- 

 teries, and of very numerous large veins, intermingled in all 

 directions, and anastomosing a multitude of times with each 



other. These branches of veins present dilatations and wide 

 36 



