BETWEEN TYPICAL REPTILES AND OTHER ANIMALS. 167 



unlike those of the Crocodile, and approximate to thoscj of clavi- 

 culate Lizards. 



The ulna and radius are relatively longer than in the Crocodile. 

 The ulna is a straight cylindrical bone enlarging at the proximal 

 end on the anterior and outer sides ; the subquadrate articulation 

 has two oblique facets, one looking upward and forward, the other 

 upward and outward toward the radius. The distal end in the 

 Crocodile is relatively smaller, and has not the same convex 

 lizard-like articulation. The proximal end of the radius is sub- 

 circular and cupped ; the distal articulation appears to be ob- 

 liquely truncated and to look backward. 



The carpal bones have nothing in common. 



The metacarpals of Chameleon are short broad bones, not un- 

 like iu form to the proximal carpals of Crocodile. The phalanges 

 of Chameleon are all of great length and strength, and so far un- 

 like the short small phalanges of the Crocodile. The digits of the 

 Crocodile are arranged in a group of three, in which their meta- 

 carpal bones overlap each other proximally, and have no distal 

 carpal ossified, and a group of two smaller outer digits articulated 

 to one distal carpal bone. If we suppose the proximal ends of 

 the metacarpals of the Crocodile to enlarge so as to thrust these 

 groups away from each other, an arrangement might be pro- 

 duced like the hand of the Chameleon. 



The pelvis of the Chameleon is unlike that of Ci'ocodiles. The 

 ilium is an elongated compressed narrow bone, shorter than the 

 scapula, and more expanded at the free end ; it descends from 

 the transverse processes of two vertebrae almost vertically, but 

 slightly forward, in a straight line with the os 'pubis, than which 

 it is slightly wider from back to front. The pubis is a short 

 straight bone almost equally expanded at both ends, entering into 

 the acetabulum for the femur and perforated in its upper third 

 ^ for the obturator nerve, like the pubic bone in Lizards. The pubes 

 are inclined to each other, and meet along the w'hole ventral mar- 

 gin of the bone, which is not the case in Crocodiles. The ischium 

 is more like that of a Crocodile in outline, ditfering in wanting 

 the process which gives attachment to the pubis, and iu being 

 longer from back to front, chiefly owing to the development for- 

 ward of the anterior distal angles. 



The Chameleon femur is about as long as the humerus, and 

 similarly has a straight cylindrical shaft more enlarged at the 

 distal and proximal ends than is the case with Crocodiles. The 



