SKELETON OF THE FROG. 73 



the same extremities of the coracoids, and supports a 

 broad "xiphoid" cartilage. 



The proximal end of the humerus, 53, is an epiphysis ; 

 the distal end presents a hemispherical ball between a 

 small external ridge, and a large internal condyloid pro- 

 cess. The antibrachial bones have coalesced, but an 

 anterior and posterior indentation at the distal half indi- 

 cates the radius, 55, and ulna, 54 ; their distal articular 

 extremities are represented by a single epiphysis. The 

 ulnar portion of the bone develops a short and broad 

 olecranon, o. The bones of the carpal series now receive 

 definite names, and are as follows: (Fig. 12), 5, sca- 

 phoid ; Z, lunare ; c and p^ cuneopisiforme ; t^ trapezium ; 

 tr^ trapezoides; m, magnum; u^ unciforme — here two 

 distinct bones. The first digit, I, has one bone, a meta- 

 carpal; the second digit, II, has a metacarpal and two 

 phalanges ; the third, III, the same ; the fourth, lY, has 

 a metacarpal and three phalanges ; and the fifth, Y, the 

 same. 



Both the proximal and the distal extremities of the 

 femur, 65, are in the condition of epiphyses. The tibia 

 and fibula are connate, 66 : a longitudinal impression on 

 the front and back part of the expanded distal end indi- 

 cates their division, but a single epiphysis, partially an- 

 chylosed, forms the proximal extremity, and a similar 

 one the distal extremit}^, of the connate bones ; they are 

 perforated near their middle, from before backwards, by 

 a vascular canal. The tarsal bones are now distinguished 

 by names. 



The astragalus, «, and calcancum, cl^ are much elongated; 

 the former is slightly bent, the latter straight ; they have 

 coalesced at their proximal and also at their distal ex- 

 tremities with each other, and with the scaphoid, 5, and 

 7 



