100 



6r. R. Wielcmd — On Marine Turtles. 



(b) Carpalia 3-5 were found in succession, and are doubt- 

 less correctly placed. 



(c) There is little doubt but that the intermedium and 

 ulnare are correctly determined, but their precise orientation 

 is not so certain. Thus it may be that the intermedium should 

 be rotated in a vertical arc of 90°. This, however, would not 

 greatly alter its general contact outline, as it is a very robust 

 and much rounded instead of flattened bone. 



(d) Since metacarpal I and the pisiform are beautifully 

 preserved, both as to form and surface markings, the possible 

 remaining margin of error as to the identity of the several 

 parts is slight. 



Figure 2. Archelon ischi/ros Wieland. Partial restoration of left front 



flipper, xig. 



R, radius ; U, ulna ; P, pisiform ; I, carpale 1 ; V, cai*pale 5. 



Description. Since the peculiarities of the humerus have 

 been quite fully dealt with in my article on the Evolution of 

 the Testudinate Humerus, this bone need not be further men- 

 tioned now, except to recall the fact that it resembles the 

 humerus of Dernioclielys more closely than any other, although 

 x diflering in some very essential features. 



The radius is only slightly longer than the ulna. Proxi- 

 mally it is triangular, and distally, rather elliptical in trans- 

 verse section. The most marked characteristic whatsoever is 

 the strong proximal bow, which recalls the lesser proximal 

 bow seen in the radius of Dermochehjs. Otherwise this form 

 has a rounder, heavier head. The proximal articular face is 

 only slightly concave, its general outline being that of an isos- 

 celes triangle, with the base in contact with the inner face of 

 the ulna. 



