202 Shufeldt on tlic Os Prominens in Hawks. 



II. p. 67.) In the same volume, page 73, in his general descrip- 

 tion of the bird-wrist, he simply describes it in the following terms : 

 " The ulnar trochlea articulates with the two free carpal bones, 

 one — the ' scapho-lunar ' — being wedged into the radial, the 

 other — ' cuneiforme ' — into the ulnar part, leaving a small 

 intermediate tract for the 'magnum' which is confluent with 

 the base of the mid-metacarpal " — not mentioning any such 

 bone, nor do we find, further on under special references to 

 certain departures in some of the genera from the general rule, 

 any allusion to such an ossicle as the os prominens. Moreover, 

 in the same work, in treating of the Muscular System of Aves, 

 page 9S, and apparently describing the muscles of a Hawk, too, 

 — Butco vulgaris. I think, — the opportunity, one would sup- 

 pose, was afforded to have called our attention to the presence or 

 absence of such a feature; but nothing of the kind has been 

 noted, the muscle being simply described (for all birds) as 

 follows : — 



"A remarkable muscle, partly analogous in its origin to the 

 clavicular portion of the deltoid, but differently inserted, is the 

 extensor plicae alar/s. ib. 30, a. b. [the Hawk] and forms one 

 of the most powerful flexors of the cubit. It is divided into two 

 portions, of which the anterior and shorter arises from the 

 internal tuberosity of the humerus ; the posterior and longer 

 from the clavicular extremity of the coracoid bone. In the 

 Ostrich and Rhea, however, both portions arise from the cor- 

 acoid. The posterior muscle, 6. sends down a long and thin 

 tendon which runs parallel with the humerus, and is inserted, 

 generally by a bifurcate extremity, into both radius and ulna. 

 The anterior muscle, «, terminates in a small tendon [the one 

 shown in the cut, for Circus, accompanying this paper] which 

 runs along the edge of the aponeurotic expansion of the wing. 

 In this situation it becomes elastic ; it then resumes its ordinary 

 tendinous structure, passes over the end of the radius, and is 

 inserted into the short confluent metacarpal, 11. It combines 

 with the preceding muscle in bending the forearm ; and further, 

 in consequence of the elasticity of its tendon, puckers up the 

 soft part of the wing." 



Professor Edward S. Morse, in his discussion upon the carpus 

 of birds (On the Tarsus and Carpus of Birds ; Ann. Lye. Nat. 

 Hist. New York, Vol. X, 1872), makes no mention of the 



