H2 D . C. W. Andrews on the 



massive and much thickened, the visceral surface between 

 tlie articulations being stronj^ly convex from before back- 

 wards, so that the symphysial surface is here very deep. 

 Anterior to this the bones are thin^ and no doubt in front 

 united with the posterior border of the clavicular arch. 

 Towards their posterior ends also the coracoids become 

 quite thin. The general form of the bones of the shoulder- 

 girdle will be best understood from PI. VIII. 



The humerus has a long straight shaft with a broad distal 

 expansion, chiefly on the posterior side, so tliat the anterior 

 border of the bone is nearly straight. The head and 

 tuberosity are well developed, and all the impressions for 

 the attachment of muscles are strongly marked, so that 

 the animal was probably adult. The bone, as a whole, is 

 proportionately very large ; it is considerably larger than 

 the femur, while in Rhomaleosaurus cramptoni the reverse is 

 said to be the case*. 



The Pelvis (PL IX.). — Thepuhes are imperfectly preserved, 

 but enough is present on one side or the other to permit of a 

 satisfactory restoration. Their broad blade has a strongly 

 convex anterior border, while posteriorly it is deeply notched 

 by the anterior border of the obturator foramen. Tlie 

 acetabular process for union with the ischium is very long. 

 In the middle line the pubes united in a long symphysis, but 

 diverged posteriorly, being probably united by cartilage with 

 one another and with the ischia — probably they had a 

 junction with these latter, completely enclosing the obturator 

 foramina. 



The ischia are very massive boues : their acetabular pro- 

 cesses for union with the pubes are very long and sharply 

 defined. The visceral surface of the united ischia is convex 

 from before backwards in fi"ont and concave behind ; 

 posteriorly these bones seem to have been abruptly trun- 

 cated. The obturator foramen is an elongated oval in 

 outline, its long axis being nearly antero-posterior. The 

 ilia are straight bones expanding towards their extremities ; 

 the ujjper expansion is considerable and is flattened, its 

 inner face must have united with some at least of the sacral 

 ribs, probably by a ligamentous union. As in the case of 

 the shoulder-girdle, the pelvis is remarkable for the massive 

 solidity of its constituent elements. 



The femur is a nearly straight bone with a distal expan- 

 sion, differing from that of the humerus in being equally 



* Lydekker, Catal. Foss. Rept. Brit. Mus. pt. ii. p. 161 (1889). 



