Thecodontosaurus and Palteosaurus. 151 



bone which is lost, which is convex from front to back and 

 does not show a very distinct outline between the pubic and 

 ischiac processes. The anterior border of the ilium is convex 

 from above downward, and the notch between it and the 

 anterior process of the ilium is more open than in the other 

 specimen. The bone is larger, has the pubic process stronger, 

 and the notch between the processes evidently less excavated, 

 so that it appears to indicate a distinct type of animal. 



? Ilium o/' Thecodontosaurus. 



Another type of ilium, if correctly identified, is referable to 

 a different genus. With this type of ilium I should be 

 disposed to associate the humerus originally figured by Riley 

 and Stutchbury [l. c. pi. xxx. fig. 1) and the fragments of 

 jaw referred to Thecodontosaurus. I have not seen any form 

 of femur which could be attributed to Thecodontosaurus^ and 

 the bulk of the remains are referable to Palceosaurus both ou 

 the grounds of osteological affinity between the several parts 

 of the skeleton and of association. 



Femur of Palaiosaurus. (Fig. 4.) 



The femur no. 67 is the type figured by the original 

 describers of Palceosaurus. As preserved it is more than 

 10 inches long, is exposed on the ventral aspect, and has a 

 slight sigmoid curve. The proximal articular surface is 

 transversely truncated and the head of the bone is convexly 

 rounded and directed inward. The transverse measurement 

 through the head of the bone outward is 2jq inches ; below 

 the head the bone contracts and the lateral contour is concave. 

 The infero-lateral trochanter, regarded as the trochanter 

 minor, begins about 2 inches below the proximal end. It is 

 a longitudinal plate, compressed from side to side, about 

 2 inches long; a slight ridge is prolonged from it down the 

 shaft towards the inner condyle. Below the lateral trochanter 

 the shaft becomes slightly narrower. It widens again in its 

 lower third, where the direction of the bone is a little down- 

 ward, so that the superior surface is convex. The inferior 

 surface of the head of tlie bone is convex from side to side, 

 and the inferior surface of the distal end is concave both in 

 length and breadth. The lateral position of the trochanter 

 minor necessarily gives an aspect of great depth in that 

 position, and the bone has an inflated aspect at the inner side 

 about the trochanter. The distal end of the bone is flattened 

 on the inner side, but rounded. The transverse width at the 



11* 



