Glass 4. Beptilia. 413- 



represented on each side by an arched, partially ossified plate, which 

 articulates below with the front edge of the sternum. A scapula 

 is distinguishable above the glenoid, and below this a coracoid, 

 which is usually divided by one or two large fenestras into two or- 

 three regions. The scapula is divided into an upper and a lower 

 portion, of which the former consists of calcified cartilage, the latter 

 of bone ; it is connected with the coracoid by a suture or is fused 

 with it. A clavicle reaches from the scapula to the epi- 

 sternum. In the Crocodilia the shoulder blade is almost 

 entirely ossified, only the upper edge being cartilaginous (supra- 

 scapula) ; the coracoid is a simple bone, and the clavicle is absent. 

 In the Ohelonia the coracoid is divided, as in the Lizards, into 

 anterior and posterior regions, which are, however, quite separate ; 

 the former, the precoracoid, is fused with the scapula, which it meets 



Pig. 339. sternum and shoulder girdle of Lacerta spread out, the scapula 

 in reality hands upwards. The right clavicle has been remoTed. a glenoid for the humerus, 

 cl olaTicle (in the species figured perforated by a large fenestra), co coracoid, co' cartila- 

 ginous epicoracoid, ep episternum, r ribs (cut away), sc scapula (here anchylosed to the 

 coracoid), sc' cartilaginous supra-scapula, .?< sternum. — Orig. 



at a right angle j the latter, the postcoracoid, is a separate bone. 

 In the O p h i d i a the shoulder girdle is altogether wanting. With 

 regard to the fore limb it must be noticed that the ulna is 

 the stronger of the two bones of the forearm. In the Ohelonia 

 the nine primitive bones are present in the carpus (sometimes 

 some are fused) ; in the Lizards, too, the carpus is little modified; 

 whilst in the Crocodilia it is distinguished by the large size of 

 the two proximal bones, and by the degeneration or fusion of 

 the distal carpals. Attached to the outer side of ,the carpus there- 

 is usually a sesamoid bone, the pisiform. The number of 



