2O4 



EXTINCT MONSTERS 



Cuvier thought, from the magnitude of their eyes, that Ptero- 

 dactyls were of nocturnal habits. " With flocks of such creatures 

 flying in the air, and shoals of no less monstrous Ichthyosauri and 

 Plesiosauri swarming in the ocean, and gigantic crocodiles and 

 tortoises crawling on the shores of the primaeval lakes and rivers 



FIG. 74. Skeleton of Pterodactylus spectabilis. 



air, sea, and land must have been strangely tenanted in these 

 early periods of our infant world." 1 



It was thought at one time that Birds differed from Pterodactyls 

 in the absence of teeth; but this only holds good for modern 

 birds. If we go back to the Mesozoic age, we find that birds 

 at that time did possess teeth. The oldest known bird, the 

 Archseopteryx, had teeth in its jaws, and presents some very 

 striking points of resemblance to reptiles (see p. 215). But if 



1 Bucklaud, Bridgewater Treatise. 



