MEMOIRS OF THE UNIVERSITY OP CALIFORNIA. 



of Palaeohatteria are seen. As near an approach to the form of the pectoral 

 girdle of a Triassic ichthyosaur as is known is found in the Proganosauria. 

 In Champsosaurus (fig. 89) the girdle is not markedly different from the ante- 



86 



88 



Fig. 86. PalaeojMtteria. Pectoral arch. Sc, scapula; Co, coracokl; Cl, clavicle; Id, interclavicle. 

 (After Credner.) 



Fig. 87. Stereosternum tumidum Cope. Pectoral arch, X 2. Sc, scapula; Co, coracoid; Id, inter- 

 clavicle; H, humerus. (After Osborn.) 



Fig. 88. Thalattosaurus alexandrae Merriam. Pectoral arch and limb, X %. Sc, scapula; Co, 

 coracoid; H, humerus; K, radius. 



Fig. 89. Champsosaurus laramiensis Brown. Pectoral arch, X % Sc, scapula; Co, coracoid. 

 (After Brown.) 



rior arch of Cymbospondylus so far as known. The scapula has nearly the 

 same form lacking only some of the distal expansion seen in Cymbospondylus. 

 The coracoid of Champsosaunis is perforated as in Cyntbospondylus, but is 

 more nearly elliptical, instead of sharply excavated on the postero-lateral bor- 



