188 WEEN THE WOBLD WAS YOUNG 



they were most like crocodiles, but in other respects, 

 again, they remind us of ostriches. To this class 

 Naturalists have given the name of Dinosaurs, from two 

 Greek words, which mean 'terrible lizards.' 



All the tribe were alike in one way, for they had four 

 legs ; but in some the structure of the bones shows that 

 the Dinosaur could, when it chose, stand upright, while 

 other varieties, such as the Brontosaur, must have been 

 compelled, or at any rate must have preferred, to walk 

 on all fours. This monstrous beast was about sixty feet 

 long, its skeleton has always been found on the bank 

 of a lake or river, and it probably fed on water plants. It 

 had a long neck, which would enable it to rear its head 

 out of the water and see whether the coast was clear of 

 its enemies, and a long tail, which was a great help in 

 swimming. But when on land it must have been difficult 

 indeed for an animal of such huge bulk to get out of the 

 way when attacked, and still more difficult for it to escape 

 detection, as every one of its tracks measures a whole 

 square yard. 



About the same time that the Brontosaurus was 

 wallowing among the reeds of the lakes and rivers which 

 covered the tract of country now called Colorado, one of 

 his distant cousins might have been met with any day in 

 the Weald of Sussex, had there been anyone living on the 

 earth to take a walk ! This particular reptile has been 

 given the name of Iguanodon, from a peculiarity of its 

 teeth. The largest kind known is thirty feet long, from 

 its nose to the end of its powerful tail, and when walking, as 

 it always did, on its hind legs, was as tall as a very big 

 elephant. "From the hollowness of its limb bones it was 

 able to move more lightly than some of the other animals 

 whose bones were solid throughout, and this was very 

 necessary, as, unlike many of these old lizards, the 

 Iguanodon had no sharp knots or spines on its skin to 

 ward off the attacks of its flesh-eating foes. So, when 

 standing as high as it did, it saw one of these huge 



