FOSSIL REPTILES 



83 



Tyranno- 

 saurus 



Trachodon 



the last and most powerful of the carnivorous dinosaurs. Like Allosaurus it 

 has enormous three-toed hind legs armed with sharp claws, 

 and smaller fore legs. Tyrannosaurus is from Montana and 

 the matrix in which it was found is as hard as flint. 

 To the left of Brontosaurus are two complete specimens of the duck- 

 billed dinosaur Trachodon. One shows the animal erect 

 and standing on guard, while the other is shown feeding on 

 shellfish and plants of the Cretaceous swamps of Montana. 



In the low case in front of this group is one of the most interesting reptile 

 specimens which has ever been discovered. It is a mummified duck- 

 billed dinosaur, Trachodon, the skin of which is wonderfully well preserved, 

 and for the first time the character of the outer covering of this animal is 

 fully revealed. The animal is lying on its back and, in spite of its crushed 

 condition, its form is easily distinguishable. It probably died on a sand 

 bank or near a shoal where the hot winds dried up the flesh until the skin 

 adhered to the bones like a close-fitting glove, and was subsequently buried 

 by a flood. 



Other specimens shown in the hall include the smaller carnivorous 

 dinosaurs, the horned dinosaurs with, in one instance at least, a skull seven 

 feet in length, and giant birds possessed of teeth. There is also the 

 finback lizard, one of the most ancient of fossil reptiles; Diadcctcs, a reptile 

 with a solid-boned skull and Eryops, a primitive amphibian. The finest 

 collection of fossil turtles in the world will be found on the south side 

 of the hall. 



Model of Xaosaurus or " Ship-Lizard, "" an ancient and grotesque reptile. Collected 

 in Texas ; length eight feet 



