THE MUSCLES OF THE UPPER EXTREMITY. Ill 



to the tendon of the tensor longus, and having a com- 

 mon insertion with it." 



If this last tendon be present in our wild pigeons, it 

 is very feebly developed and consequently easily over- 

 looked. I did not detect it in the Dove above alluded 

 to, and must believe it was absent in that particular 

 specimen. Wherever I examined it, it has invariably 

 agreed with Garrod's description of it. 



Now what I have said above in reference to the dissec- 

 tion of these muscles in the Eaven, applies with equal 

 truth to any bird. Let us choose for our purpose an 

 oriole, for instance, and in that species the tensor patagii 

 longus, tensor patagii brevis and dermo-tensor patagii 

 all occur. Having secured a good specimen of some such 

 bird, pluck it perfectly clean, being careful, in removing 

 the feathers of the wings, that you do not tear the skin 

 (Fig. 35 quat.). Now with a small, sharp dissecting 

 scalpel make an incision just through the integuments 

 and no more, along the line which I have indicated by 

 the letters inc. in Fig. 35 quat., and then carefully and 

 completely reflect this skin-flap in both directions until 

 all the superficial muscles of the arm and forearm are 

 exposed, even to the tendon which extends from the 

 shoulder to the wrist (tp. L), in the free margin of the 

 duplicature of the skin in which these muscles are found. 

 By practice we soon learn the best way of doing this, 

 and in the case of all ordinary sized birds, our left hand 

 soon learns how to hold the wing in such a way that the 

 parts to be examined are kept on the stretch, thus faci- 

 litating our examinations and study, which latter may 

 now be undertaken. 



Professor Garrod chose the wing of Icterus vulgaris 

 to illustrate the arrangement of the patagial muscles in the 

 Passeres, and it will be seen by an examination of his 



