92 THE BONES. 



Faces. The external or superior face, studded with some muscular 

 imprints, is excavated on both sides, and is named the external iliac fosssa. 

 The internal or inferior face offers for study : 1, An external portion, 

 smooth, and crossed by some vascular grooves; this is the iliac surface, 

 which is replaced in Man by an excavation called the internal iliac fossa ; 

 2, An internal portion, roughened and uneven, presents, posteriorly, the 

 auricular facet, an irregular diarthrodial surface, elongated from side to 

 side, a little oblique in front and inwards, and responding to an analogous 

 surface on the sacrum. 



Borders* The anterior border, or crest of the ilium, is slightly concave, 



Fig. 58. * 



THE COX.E; SEEN FROM BELOW. 



1, Iliac surface ; 2, Auricular facet; 3, Angle or crest of the ilium; 4, Angle 

 of the haunch 5, Cotyloid cavity ; 6, Its bottom ; 7, One of the imprints 

 for the insertion of the anterior straight muscle of the thigh (rectus femoris); 

 8. llio-pectineal ridge; 9, Channel on the external face of the pubes ; 10, Oval 

 (or obturator) foramen; 11, Ischial spine; 12, 12, Ischial arch. 



and bears a roughened lip for muscular insertion. The external border is 

 thick, concave, and furrowed by vascular fissures ; it presents, inferiorly, the 

 nutrient foramen The internal border is thin and concave, particularly in 

 its posterior part, which constitutes the great ischiatic notch. 



Angles. The external angle, or anterior and superior spinous process, is 

 thick, wide, and flat, and bears four tuberosities : two superior and two 

 inferior, The internal angle, or posterior and superior spinous process, 

 represents a rugged tuberosity curved backwards and upwards. 1 The 



( ! At the external angle of the ilium, there is sometimes found in the horse a process . 

 often a very marked one directed downwards, and completely enveloped by the external 

 ilio-femoral muscle.) 



