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1. M. trapezius, 0*10 oz. 



Origin ; from the occipital and cervical scutes, as far back as the 



shoulder joint. 

 Insertion ; into the anterior edge of the acromion. 



2. M, latissimus dor si Qiumerodor satis), . . . . . . . 0*12 oz. 



Origin ; from the four anterior dorsal scutes. 



Insertion ; into the back of the humerus, having its tendon con- 

 joined with that of the teres major. \ 



3. If. teres major, 0*02 oz. 



Origin ; posterior superior portion of scapula. 

 Insertion ; with latissimus dorsi. 



4. M. sterno-atlanticus, 0*22 oz. 



Origin; from the sternum, in front of its articulation with the 

 coracoid. 



Insertion ; into the side of the atlas. 



5. M. pectoralis major, . . 0*77 oz. 



Origin ; from top of sternum, and its entire length, and from the 

 abdominal ribs two-thirds of the distance to the pelvis. 



Insertion ; into the outer edge of the great pectoral ridge of the hu- 

 merus. 



6. M. pectoralis minor, 0*04 oz. 



Origin ; from the outer surface of the acromion and coracoid, lying 



under the tendon of the biceps humeri. 

 Insertion ; inner side of pectoral ridge. 

 In this muscle is also included the supraspinatus, which is repre- 

 sented by the portion of the muscle taking its origin from the scapular 

 border of the acromion, inside the origin of the deltoid. These two pec- 

 torals draw the arm forward in swimming. 



7. M. pectoralis secundus, 0*04 oz. 



Origin ; from the first sternal rib. 

 Insertion ; into the posterior edge of the coracoid. 



This muscle draws the arm backwards, by acting on the coracoid, 

 and may represent the second pectoral of birds. 



8. M. sternomastoideus, 0*17 oz. 



Origin ; from top of sternum. 



Insertion; into the posterior third of inner side of lower jaw. 



9. M. Omo-hyoideus, 0-06 oz. 



Origin ; from the acromion, just above the glenoid cavity. 

 Insertion ; into the descending wing of the hyoid bone. 



10. M. deltoideus, 0*15 oz. 



Origin ; from a broad rim of the acromion, and from the inner sur- 



face of the acromion, winding out over the edge to form the 



inner portion the deltoid. 

 Insertion; into the deltoid ridge of the humerus. 



11. M. infraspinatus, 0*02 oz. 



Origin ; from the outer surface of the scapula, which is altogether 



occupied by this muscle and the teres major. 



