272 HISTORICAL GEOLOGY 



the end of the tail was expanded into a sort of rudder. Many 

 wonderfully preserved specimens of Pterosaurs have been found, 



Fig. 173 



An Ornithopod, Claosaurus annectens, of the Dinosaur 

 division of Mesozoic Reptiles. Length over 20 feet. 

 (Skeleton restored by March.) 



some with even the wing membranes preserved. Pterosaurs ranged 

 from the late Triassic to the close of the Mesozoic. 



Fig. 174 



A Rhamphorhynchus of the Pterosaur division of Mesozoic Reptiles. 

 Spread of wing about 2 feet. (Restored by Marsh.) 



