THE RABBIT. 283 



the acetabulum, 1 a deeply concave articular surface on 

 the external face of the innominate bone. The ilium 

 presents a ventral (pre-axial) pubic border, a dorsal 

 (post-axial) ischial border, an external acetabular 

 border consisting of an inconspicuous ridge running from 

 the acetabulum along its outer surface, and an anterior 

 (dorsal) supra-iliac border along its free end : that portion 

 of its external surface on the ventral side of the acetabular 

 border is the iliac fossa, that on its dorsal side the 

 gluteal fossa ; its inner surface is the sacral fossa. 

 The pubes of opposite sides unite with one another in 

 the middle line, by synchondrosis, to form the symphysis 

 pubis : the posterior part of the ischium is expanded and 

 roughened, forming its tuberosity (tuber ischii). 



92. If the hind-limb be compared with that of the Lizard 

 (p. 151 1 08), it will be seen that the femur, and with it 

 the whole limb, has undergone rotation forwards : as a con- 

 sequence of this the hind-limb is, like the fore-limb, 

 brought into a plane parallel with the median vertical plane 

 of the body, but, the rotation being in the opposite direc- 

 tion, the pre-axial border is internal in the whole limb, and 

 the originally dorsal surface looks, on the v;hole, forwards. 



93. The femur, the long axis of which, in the natural 

 position, is directed downwards and forwards, so that its 

 originally dorsal surface looks upwards and forwards, and its 

 pre-axial border inwards. Its proximal extremity presents 

 a rounded, projecting head on its pre-axial (inner) border, 

 for articulation with the acetabulum ; a large process, the 

 greater trochanter, just external to the head; a pit, the 

 trochanteric fossa, on the ventral surface, bounded 

 pre-axially by the great trochanter ; a lesser trochanter 



1 The pubis proper is really shut out from the acetabulum by a small 

 epiphysis, the cotyloid bone. 



