1867.] 



:OLOGY OF IGUANA TUBERCULATA. 



775 



The dorsal mass or supracauJal muscle is in part the continuation 

 backwards of the sacro-lumbalis, in part takes fresh origin from the 

 posterior surface of the ilium. It extends backwards also to about 

 the thirteenth caudal vertebra. 



Fig. 6. 



Superficial muscles of front of thorax, of inside of right arm, and of flexor 

 siu'face of right forearm. 



D. Biceps. B. A. Brachialis anticus. C. B. 2. Second or long part of coraco- 

 brachialis. D. 1. First part of deltoid. E. 0. External oblique. E. U. 

 Estcn.sor carpi ulnaris. F. P.D.I. Fir.st part of flexor profundus digitoruni. 

 'F. P. D. 2. Second part of flexor profundus digitorum. F. B. Flexor carpi 

 radiaUs. F. S. D. Flexor sublimis digitorum. P. Pectoralis. P. T. Pro- 

 nator teres. B. Rectus abdominis. 8. C. M. Stemo-cleido-mastoid. S. L. 

 Supinator longus. T. 4. Fourth jjart of the triceps. 



Muscles of the Pectoral Limb. 



Pectoralis major (iigs. 1, 2, 6, 8 & 10, P.). This muscle is largely 

 developed, and arises from the sternal part of the si.\th thoracic rib, 

 and from the sternum and interclavicle, from the posterior end of 

 the former to the anterior extremity of the latter. 



From this extensive origin its fibres converge, and are inserted into 

 the most prominent part of the radial tuberosity of the humerus, 

 just opposite the insertion of the deltoid, but separated from the 



