202 
Shufeldt on the 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 4 scapho-lunar ’ — being wedged into the radial, the 
other — 4 cunei forme ’ — 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 98, and apparently describing the muscles of a Hawk, too, 
— Buteo 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 plicce alaris , 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, b , 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, <2, 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, u. 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. Lyc. Nat. 
Hist. New York, Vol. X, 1872), makes no mention of the 
