THE MUSCLES. . 157 



281. Fascia perinsei. 



The general subcutaneous fascia is connected before with Tu- 

 nica dartos (or the fibro-cellular tissue of the labia), behind with 

 the sphincter ani and coccyx ; is near the anus membranous, 

 contains fat, and is placed over the fossa perinsei. 



282. a. The proper perinaeal fascia (f. p. superficial.) has an 

 anterior and a posterior segment. 



1. Anterior segment (aponeur. ischio-pubica), from arcus pubis 

 of the Ischium and pubis as far as tuber ischii, covers in the 

 male : m. transv. (superf.), ischio-cavern., and bulbo-cavernos., 

 and passes over anteriorly upon the Penis ; in the female it di- 

 vides anteriorly, covers with the internal layer the constrictor 

 vaginas, reaches in the labium min. as far as the clitoris; the ex- 

 ternal lies in the entire length of the labia major a. 



2. Posterior segment (apon. ischio-rectalis) connected in front 

 with, 1. ; covers the fossa perinsei ; the internal layer covers the 

 external surface of the lev. and sphincter ani; the external the 

 posterior part of the obturator intern., and confined below to the 

 tuber ischii, lig. tuberoso-sacrum and glutxus maximus. 



Fossa perinsei [Ischio-rectal fossa], a conical fossa, the base of 

 which corresponds with the skin, is formed, anteriorly, by transv. 

 perin., behind by the inferior border of glutseus maximus, inter- 

 nally by levator ani, externally by tuber Ischii. It is filled up 

 with fat and fibrous striae. 



283. b. Lig. perinseale, s. fascia perin&i profunda, a three- 

 sided ligament ; closes the anterior portion of the pelvic outlet (as, 

 levat. ani the posterior), is perforated by the urethra; arises from 

 os Pubis and Ischium, between lig. arcuatum (in front) and m. 

 ischio-cavernos. (behind) ; below nerv. and art. penis. The an- 

 terior portion, covered with venous plexuses, lies above and at the 

 sides of pars membran. urethras (presenting an obstruction in 

 catheterism) ; the posterior portion lies below the urethra. , 



284. c. Fascia pelvis lines the cavity of the small pelvis. 

 Or. : close before arcus pubis ligamentous (lig. pubo-vesicale), 

 inch from that of the other side, so that an oval fossa remains 

 between the ligaments and collum vesicas, where they unite ; far- 

 ther, from pars horizontal, of os pubis; at the superior angle of 

 for. obturator, an opening remains (for nerv. and vasa obtura- 

 tor.) ; then from linea arcuataas far as to symphys. sacro-iliaca. 

 Ins.: as far as the origin of lev. ani single; it then divides ; the 

 anterior portion passing on the side of the urinary bladder, Pros- 

 tate (vagina), and rectum; the posterior, behind the rectum, to 

 the middle line, as far as the os coccygis. 



