86 THE OPEN BOOK OF NATURE 
reptiles of Triassic age are of more popular interest. 
It was in that Period that the long extinct order of 
Deinosaurs (Greek, deinos=terrible, and sauros= 
lizard) appeared. Had we lived in their age and 
met them on our rambles I have no doubt we should 
have thought the name that men have given them is 
fully justified. They must have presented a truly 
terrible appearance. They would be the monarchs 
of the earth at the time when they flourished. Most 
of them were of great size, resembling rhinoceroses 
and elephants in this respect. While they appeared 
in Triassic times, they attained greater development 
in the Jurassic Period. The Iguanodon (possessing 
teeth like those of the modern iguana, a land- 
lizard) was among the first discovered Deinosaurs, 
and when I tell you that it measured about twenty- 
four feet from the snout to the end of the tail, and 
that its head was poised about fourteen feet from 
the ground, you will realize that it was a beast of 
some size and power. It had a pair of long, power- 
ful hind-legs and a pair of somewhat shorter and 
less sturdy front-legs. Its remains show that it 
would walk like a kangaroo ; footprints left by the 
animal and preserved in the strata prove this. A 
huge thigh-bone, bigger than that of the greatest 
elephant, of another Deinosaur has been found in 
the United States ; it belonged to the Atlantosaurus, 
which is estimated to have been nearly twice the 
size of the iguanodon. The Megalosaurus (Greek, 
megas = great, and sauros = lizard) was about twenty. 
five feet long. It was carnivorous—that is to say, 
a flesh-eater—and it not unlikely preyed upon its 
weaker relatives, some of whom were vegetarians. 
