369 



continued over the transverse muscles, and folding around their 

 edges is prolonged upwards into the ischio-rectal fossa. 



It also sends off, from its upper surface, membranous septa between 

 the accelerator muscles in the middle, and the erectors on either 

 side, to join the triangular ligament, and thus forms three distinct 

 and independent sheaths that are confounded anteriorly with the 

 common sheath investing the corpus cavernosum. 



M. Velpeau's description of this fascia (Traite d' 'Anatomie Chir., 

 3me edit. Paris, 1837, tome ii. p. 214) is the most minute and accu- 

 rate. He says of it, in addition to the above — " that it is insensibly 

 lost in front upon the body of the penis." Mr. T. Morton (in his 

 Treatise on the Surgical Anatomy of the Perineum, London, 1838, 

 p. 12) says of it, that — " anteriorly it passes forwards into the scro- 

 tum, where it appears to become continuous with the dartos." 



Colles, who has given the most accurate description of the sheath 

 of the penis (in his Treatise on /Surgical Anatomy, 2d Amer. edit., 

 Phila., 1831, p. 146) says — " on raising the skin we find a ligament- 

 ous membrane which invests the penis, and which is derived from 

 the suspensory ligament:" further on he adds — "This ligament, ad- 

 hering by its upper edge to the symphysis pubis, descends and fixes 

 itself by its lower edge to the dorsum penis, but it does not cease 

 here, for it can be traced, expanding itself over the crura of the 

 penis and urethra, until it terminates at the base of the glans, thus 

 constituting one of the envelopes of the penis." 



Other modern anatomists, such as Malgaigne, Cruveilhier, A. Be- 

 rard, &c, have contributed nothing to render our knowledge of these 

 parts more complete than the authorities just quoted. 



The present statement, besides embracing what has been described 

 by Velpeau and Colles, shows the peculiar relations of this sheath 

 to the corpus spongiosum urethras and the glans penis, which, so far 

 as my researches have extended, have not hitherto been described 

 by anatomists. 



Important pathological relations have been shown by Velpeau to 

 depend on the peculiar structure of these parts as described by him- 

 self, especially in the formation of abscesses, and extravasation of 

 urine anterior to the triangular ligament. The more complete de- 

 velopment of their anatomical relations set forth in this paper, serves 

 to confirm these pathological views, and throw additional light upon 

 them. 



The following case of extravasation affords a good illustration. 



