TIIK rosTEimni I. 



93 



posterior or cofylolil angle is prismatic and very voluminous. It exhibits : 

 1, Behind, a wide concave articular facet, which forms part of tho cotyloid 

 :y; 2, Above this cavity, tho supracotyloid crest, represented in 

 3Ian by tho ischiutlc *pine. This is an eminence elongated from before to 

 In-hind, sharp on its summit, smooth inwardly, roughened outwardly, and 

 continuous by its anterior extremity with the internal border of tho bone ; 



3, Outwardly, two deep imprints for tho insertion of tho rectus muscle; 



4, In front and inwards, the ilio-pectineal eminence, a small elongated pro- 

 niini-uce forming the most salient point of a kind of ridge (linea ilio-pectinea) 

 that insensibly subsides above on the inner face of the ilium, and is continued 

 below by the anterior border of the pubis. 



Of the three angles of the ilium, the first is also termed the angle of the 



'(. and the second the angle of the croup. 

 POBLS. Situated between the ilium and ischium, elongated from side to 



Fig. 59. 



IT.I.VIS; FROST vu:\v. 



1. Civ.t ;md anterior spinous process of the ilium ; 2, Angle of the croup, with the 

 auricular facets proceeding from it ; 3, Shaft of the ilium, with the ilio-pectineal 

 crest ; 4, Cotyloid cavity ; 5, Symphysis pubis ; 6, Ischiatic tuberosity. 



side, flattened above and below, and irregularly triangular, the pubis, the 

 smallest of the three divisions, is divided for convenience of description into 

 two faces, three borders, and three angles. 



Faces. The superior, smooth and concave, concurs in forming the floor 

 of the pelvis. It shows one or two nutrient ioramiua. Tin- //// -rlor is 

 roughened, and marked throughout its length by a wide channel which 

 reaches the bottom of the cotyloid cavity. This fissure lodges the puhio- 

 fomoral ligament and a very largo vein. 



Borders. The anterior is constituted by a thin rugged lij, which is 

 curvi-d upwards. Tho posterior, thick and concave, circumscribes anteriorly 

 a wide opening, the oval, siibpubic, or obturator foramen ; it is channeled near 

 tin- cotyloid angle by a fissure which runs obliquely inwards and down- 

 u mis. The internal is united with that of the opposite pubis to form tho 

 pubic portion of tho pelvic symphysis. 



