THE ABDOMEN 647 



of lumbar glands. For the deep lymphatics of the antero-lateral 

 abdominal wall, see p. 664. 



Penis. Coverings. — The skin at the free extremity of the 

 glans, being doubled upon itself, passes backwards until it reaches 

 the constriction behind the corona glandis called the cervix. Here 

 it is reflected forwards, closely investing the cervix, corona glandis, 

 and body of the glans. On reaching the lips of the meatus urinarius 

 it becomes continuous with the mucous membrane of the urethra. 

 The skin covering the glans is provided with papillae, but these 

 do not appear on the surface. The duplicature, which the skin 

 forms in the region of the glans, is called the prapidiiim penis, or 

 prepuce. The under part of the prepuce is connected to the imder 

 surface of the glans by a median, laterally compressed, triangular 

 fold, called the frenum prcepiitii, which extends as far as the lower 

 pai t of the meatus urinarius. The skin of the cervix, corona 

 glandis, and adjacent part of the inner surface of the prepuce 

 contains large sebaceous glands, called the glands of Tyson. Their 

 secretion is a whitish curdy substance, and is strongly odorous, 

 from. which character the glands have been called the glanditicB 

 odorifercB, the secretion being called the smegma prcBpuiii (unguent 

 of the prepuce). The dartos tunic is situated immediately beneath 

 the skin, and is destitute of adipose tissue. It is continuous with 

 Camper's and Scarpa's fascise of the anterior abdominal wall, and 

 with the tunica dartos of the scrotum, like which latter it contains 

 involuntary muscular tissue. The fascial investment or sheath 

 covers the penis, with the exception of the glans. It is situated 

 beneath the dartos tunic, and at the cervix blends with the skin 

 of the glans. Towards the root of the organ it receives expansions 

 from the ischio-cavemosi and bulbo-cavernosi, and it covers the 

 dorsal vessels and nerves. In this way the dorsal vein is com- 

 pressed during the action of the ischio-cavemosi and bulbo- 

 cavernosi. At the root of the organ the fascial investment blends 

 with the two layers of the suspensory ligament. 



Suspensory Ligament. — ^This ligament, which is strong and tri- 

 angular, is composed of fibrous and elastic tissues. It is attached 

 superiorly to the front of the symphysis pubis, where it is single, 

 and interiorly it divides into two laterally-disposed, diverging 

 laminae, which blend with the fascial sheath of the penis. The 

 interval between the two laminae is occupied by the dorsal vessels 

 and nerves. 



The dorsal arteries. — For the description of these arteries, see p. 624. 



In addition to the dorsal artery, the integument of the organ 

 is supplied by the superior or superficial external pudic arteries, 

 the branch from each of these vessels lying external to the dorsaUs 

 penis artery. 



Deep Dorsal Vein. — ^The tributaries which give rise to this vein 

 come from the glans and corpora cavernosa. They form at first two 

 dorsal veins, but these soon imite into one vessel, which passes 

 backwards in the middle line, occup^ang the g?oove between the 

 corpora cavernosa, where it is under cover of the fascial sheath 



