230 REPTILIA. 



limb is large, though very feeble. The pubic bones are fused at their 

 symphysis. The femur is much shorter than the tibia, considerably 

 curved, with a slender neck set at only a slight angle with the shaft, a 

 nearly spherical head, and a small trochanter. The tibia has no con- 

 spicuous cnemial crest. There are two or three elements in the tarsus, 

 and the fifth digit is rudimentary or absent. The typical species is 

 Pteranodon longiceps (fig. 140), with skull O76 m. in length ; P. ingens is 

 still larger. These and other forms are represented by large portions of 

 skeletons from the Chalk of Kansas. 



Isolated bones, mostly in a very imperfect state, represent 

 Pteranodon and its allies in the Cambridge Greensand and 

 other European Cretaceous formations. Some specimens show 

 the characteristic articulation of the scapula with the spines 

 of the fused anterior dorsal vertebrae. Some exhibit formid- 

 able teeth (Ornithochirus), others appear to have been toothless 

 (Ornithostoma). 



