Ml'MMIKD 1)L\()SMI{ 



107 



Trachodon 



shellfish aiK 



Mummied 

 Dinosaur 



To the Ict'l of nr()iitt)saurii.s Jirc two coiiiplctc .six'ciiiicns of ilif diick- 

 bilh'd dinosaur Trachodon. One shows the animal erect 

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

 plants of the Cretaceous swamps of Montana. 



Most wonderful, perhaps of all the si)eeimens shown 

 here is a "niuniniy" of Trachodon in which the texture 

 of the skin is preserved. 



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 w^as subsequently buried by a 

 flood. 





Section of the skin of Trachodon showing the small scutes with which the animal was covered. 

 About natural size 



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 ; Diadedes, 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. 



In the Tower of the Southeast Pavilion are displayed the fossil fishes 

 which belong to a much earlier period than the mammals 

 and reptiles, some of them having lived tw^enty to fifty 

 millions of 3^ears ago. Many of these forerunners of back- 

 boned animals are quite unlike any living fishes and are probably only very 

 indirectly related to them; some were small, curiously encased in shells; 



Fossil Fishes 



