210 THE WORLD OF LIFE CHAP. 



The illustration of the skeleton of one of these early 

 forms on the preceding page is of the natural size (Fig. 63). 

 It shows the greatly elongated fifth finger to which the 

 wing-membrane was attached. In this form there were 

 small teeth in the jaws, and the tail was very short. 



FIG. 64. RESTORATION OF A LONG-TAILED PTERODACTYL 



(Rkamphorhynchus phyllurus). 



From the Upper Jurassic of Bavaria. (B.M. Guide.) Expanse of wings more 

 than 2 feet. The long tail has a terminal web, shown in casts in fine litho- 

 graphic stone. 



The above restoration (Fig. 64), shows a larger species 

 from the Jurassic formation, at which period they were more 

 varied. This had a very long tail with a dilated membrane 

 at its tip. Allied species, with a long pointed tail, have been 

 found in the Lias of Lyme Regis, and also at Whitby. 



FIG. 65. TOOTHLESS PTERODACTYL (Pteranodon occidentalis). 

 From the Upper Cretaceous of Kansas, U.S.A. (B.M. Guide.) 



It was not till the Cretaceous period that the Pterodactyls 

 reached their greatest size, the species figured here having 

 an expanse of eighteen feet ; and these large forms have a 

 powerful but toothless beak (Fig. 65). 



