XIIL STENEOSA UR US. 383 



Of the bone represented by figs, i and 3 three specimens have 



Diagram CLXXXVI. Steneosaurus palpebrosus (?). 



I. Humerus (right), seen internally. 2. The same, seen externally. 3. Tibia, 

 right side, seen externally. 4. The same, seen posteriorly. 5. The same, seen 

 anteriorly. 6. Outline of distal condyle (a. anterior). 7. Outline of proximal 

 condyle (a. anterior). 



come to us with many portions of steneosaurus. It appears to be a 

 humerus, in which still remain traces of a crocodilian type, though 

 the whole is shortened, the proportions are altered, perhaps to a 

 more decidedly aquatic adaptation. The upper part is concave in- 



Diagram CLXXXVII. Steneosaurus palpebrosus. Scale one-tenth of nature. 

 The right ischium, seen from below. 



ternally, and convex outwardly, and much roughened by tendinous 

 attachment, as is likewise the lower more uniformly convex end, 

 which has two unequal facets somewhat obscurely marked. What 

 appears to represent the deltoid crest is traceable in the upper part. 

 The pelvic girdle is only partially known by the right ischium. 



