1867.] MYOLOGY OF IGUANA TUBERCULATA. 



Fig. 1. 



707 



Superficial muscles of outer side of thorax and arm, and of extensor surface of fore- 

 arm, — the gular pouch being cut to show more of the sterno-cleido-mastoid. 



B. Biceps. B. ^. Brachialis anticus. D. 1. First pai-t of deltoid. 7). 2. Second 

 part of deltoid. D. M. Depressor mandibukc. E. 0. External oblique. 

 E. 7?. Extensor carpi radialis. E. U. Extensor car])i ulnaris. F. U. Flexor 

 carpi ulnaris. L. D. Latissimus dorsi. M. H. Mylo-hyoid. P. Pectoralis 

 major. P. My. Platysma niyoides. & C. M. Stemo-cleido-mastoid. 8. L. 

 Su^jinator lougus. Tg. Trapezius. 



Muscles of the Head and Trunk. 



Mylo-hyoid (fig. 1, M. H.). This is a thin muscular layer, arising 

 from the outside of the posterior part of the mandible and from the 

 inferior margin of the middle and more anterior portion of the bone. 

 It does not, however, extend to its anterior end. Descending inside 

 the skin of the gular pouch its fibres gradually become lost. 



Fibres similarly disposed below, but ending above in the fascia 



