232 MARSHALL— A STUDY OF THE [June 19, 



pollex digit and os magnum. It is inserted tendinously on the 

 proximal ridge of the pollex digit. 



E. This is a short, stout muscle arising from the ventral and 

 dorsal end of the coracoid. It passes directly over to the head of 

 the humerus where it is inserted, one point of the insertion ex- 

 tending down to the anterior border of the humeral crest. The 

 long tendon of the biceps passes over this muscle, which does not 

 appear on the plates. 



2. Posterior extremity. 



Here are described only those muscles that insert upon and arise 

 from the femur. The hind limb is so weak in this species and its 

 other muscles so delicate, that it did not seem worth the time to 

 work out its whole musculature. They are described in the order 

 of their occurrence, beginning with the superficial. 



i. M. ilio-tibialis intemus or Sartorius {II. tib. int., PI. VI, 

 Figs. 31, 34, 35). This is the most anterior muscle of the thigh, 

 of those extending from pelvis to femur. It comes fleshily from the 

 dorso-lateral border of the ilium and covers the posterior origin of 

 the posterior portion of the latissimus dorsi, and the anterior edge 

 of the ilio-trochanterici. It runs free from the muscles of the 

 pelvis behind it to the femur, gradually diminishing in size and ter- 

 minating in a flat tendon on the inner surface of the knee joint 

 where it is covered by a lower leg muscle. 



2. M. ilio-trochanterici {It. troch., PI. VI, Figs. 31, 35). 

 This large, somewhat pyramidal-shaped muscle arises fleshily from 

 the region of the acetabulum and that portion of the preacetabular 

 ilium not occupied by the sartorius, the fibers extending even to 

 its ventral border. These converge and insert by a thin tendon on 

 the trochanter where it is covered by the m. ilio-tibialis. It has 

 not the divisions given by Gadow (/. c. ), but is a compact muscle. 



3. M. ilio-tibialis (PI. VI, Figs. 31, 34, 35). This thin, broad 

 muscle is the most superficial one of the thigh. It springs semi- 

 tendinously from the acetabular and post-acetabular ilium. It 

 consists of an anterior and posterior portion which are readily dis- 

 tinguished. The anterior portion (//. tib. ant.) extends about two 

 thirds the length of the femur, then merges with the underlying 

 muscle. The posterior portion (//. tib. post.) diminishes in width 

 distally and inserts aponeurotically upon the muscles covering the 

 outer surface of the knee joint. 



