MYOLOGY . 99 



the dorsal vertebrae and attach to each succeeding rib. Those in 

 front are best developed. 



Shape, Thin and triangular. 



Relations. External to the intercostales. 



Action. Aids in respiration. 



Appendico-costales (Fig. 24, No. i). Location. The lateral side 

 of the thorax. 



Origin and Insertion. From the posterior edge of an uncinate 

 process or epineural appendage, the fibers extending downward 

 and backward to the outer surface of the succeeding rib. 



Shape.- A series of thin triangular-shaped muscles. 



Relations. Internally, with the intercostales. 



Action. Aids in respiration. 



THE ANTERIOR PECTORAL GROUP 



Tensor patagii longus Tensor patagii brevis 



Tensor Patagii Longus (Fig. 15(7, No. i; Fig. 14, No. 2). Loca- 

 tion. Anterior shoulder region, in the triangular patagium of the 

 wing. 



Origin. By a flat tendon common to it and the tensor patagii 

 brevis from the supero-mesial line of the head of the clavicle. 



Insertion. By a long slender tendon extending in the duplicature 

 of the patagium, with which the fibers blend. Passing to the side 

 of the extensor metacarpi radialis longus, it extends over the end 

 of the radius and is inserted to the os carpi radiale, and to the fascia 

 which binds down the other tendons on the anterior part of the wrist- 

 joint. 



Shape. Cone-shaped belly terminating in a long tendon. 



Relations. Externally, with the skin; by its tendon, with the 

 border of the extensor metacarpi radialis longior. 



A ction ^Tenses the soft part in the fold of the wing, and aids in 

 flexing the forearm. 



Tensor Patagii Brevis (Fig. 14, No. 3). Location. In the trian- 

 gular patagium of the wing. 



Origin. From the head of the clavicle in common with the 

 preceding. 



Insertion. The tendon bifurcates, one branch blending with the 

 fascia of the extensor metacarpi radialis longior, the other inserting 

 just below the tubercle on the external condyle of the humerus. 



