50 Department of Vertebrate Paleontology. 



26. Great Irish Deer Megaceros. 



Pleistocene Epoch. Ein-ope. 



Drawn from the skeleton mounted in the American Museum. 



Megaceros exceeded any living deer in the spread of its 

 antlers, in some cases ten or even eleven feet from tip to tip. 

 In size it is about equalled b}'' the Moose, but the proportions 

 were somewhat different, approaching those of the Fallow 

 Deer {Cervns dama) to which it was more nearly related. The 

 most abundant and complete remains have been found in the 

 bogs of Ireland, but the animal rangeil all over Western 

 Europe. It is not found in America. 



27. Primitive Mastodon Trilophodon. 



Miocene Epoch. 



Based upon a skull and incomplete skeleton in the American 

 Museum, and upon the restored skeleton of T. aiigastidens by 

 Prof. Gaudry. These Miocene ancestors of the Mastodons and 

 Elephants were much less specialized than their later de- 

 scendants. This is especially seen in the small tusks in both 

 upper and lower jaws, the upper ones curving down, the 

 lower ones straight, and both with an external or anterior 

 enamel band like the incisors of rodents, — in the shorter 

 trunk, as indicated by the characters of the skull, in the limbs 

 of moderate length and toes much less reduced than in the 

 Pliocene and Pleistocene proboscidians. 



28. Great Carnivorous Dinosaur Allosaurus. 



Upper Jurassic Period. 



This great carnivorous reptile was a contemporary of the 

 huge Sauropoda. That it preyed on their carcasses is certain, 

 for the bones are often found fossil with scorings and scratches 

 on their softer surfaces which might well have been made by 

 this animal, and its broken-ofif teeth, still more frequently 

 found close by, suggest that it was more greedy than prudent 

 in its feasts. But the Allosaurus was likewise well adapted in 



