170 MB. H. a. SEELEY Olf OSSEOUS HESEMBLANCES 



Crocodiles, a T-sliaped or + -shaped episternum, and clavicles. 

 The coracoid is more like the Chameleon's than the Crocodile's 

 in form, but differs from both in its anterior emargination and 

 processes directed towards the episternum. The scapula is most 

 like that of the Dragon. Stellio and Polychrus approximate in 

 having the bone narrow ; but in most Lizards the bone has an 

 expanded and emarginate form, or even unites along its anterior 

 side with the coracoid. 



The humerus is broader at both ends than a Crocodile's. The 

 radial process is thick and blunt, and does not make an angle with 

 the upper surface of the bone, as it does in Chameleon and Cro- 

 codile, though in the limbs the Chameleon is less closely ap- 

 proached by the adult Alligator than by the young animal. 



The distal end of the humerus in Lizards has three condyles, of 

 which the middle one is usually most developed. The humerus of 

 the Dragon seems more like the Chameleon's than the Crocodile's, 

 but has the radial crest smaller. 



The ulna resembles the Crocodile's in being compressed from 

 side to side, though it is even more compressed ; but it differs in 

 the development of an oblique olecranon ossicle, which gives to 

 the bone a testudinate form. The distal end is expanded, with 

 the articulation subhemispherical and convex from side to 

 side as in the Chameleon, and not convex from front to back as 

 in the Crocodile. The ulna is not so long as the humerus ; but, 

 owing to the development of the olecranon, the disproportion is 

 not usually so marked as in the Crocodile. In the Skink the pro- 

 portion of the forearm is most Crocodilian. 



The radius is a not dissimilar bone to that of the Crocodile ; 

 only in Crocodile the proximal end is concave, and the part of 

 the distal articulation which is most prolonged becomes a promi- 

 nent boss. 



The carpal bones are not conformable. 



The metacarpals and phalanges are not dissimilar, and differ 

 chiefly in Lizards having the claw-phalanges compressed from 

 side to side. 



The pelvis of Lizards is very uniform, and, both in its en- 

 tirety and in the forms of the constituent bones, is very unlike 

 that of the Crocodile. The pubis, like the coracoid, is usually 

 perforated ; it enters into the acetabulum for the femur, and 

 develops a prepubic process. The posterior end of the ilium 

 is more prolonged backward, and the anterior ventral angle of 



