THE MIGHTY DINOSAURS 19 



and slender teeth, among which were no grinders, 

 were adapted only to soft food, and he undoubtedly 

 lived on the juicy plants that were then so abundant. 

 For in those days the western portion of North 

 America, where Diplodocus made his home, was not 

 a mountainous country. Instead, it was level and 

 made up largely of swampy ground, lakes, and 

 slowly flowing streams. The climate and vegeta- 

 tion were tropical; and this was the case in all the 

 other sections of the world where the Dinosaurs 

 lived. 



Although Diplodocus was such an enormous 

 creature, he had a brain that was not much bigger 

 than a walnut. So he must have been as stupid 

 as he was awkward. All the Dinosaurs, for that 

 matter, seem to have been sadly lacking in intelli- 

 gence. The name Morosaurus (Stupid Lizard) has 

 been given to one species. Another species, called 

 Brontosaurus, although of tremendous size, was pro- 

 vided with but a tiny brain. The man who named 

 this creature Thunder Lizard, for that is what 

 Brontosaurus means, must have been thinking of 

 the sound which the animal made when he walked, 



