736 



THE AMERICAN NATURALIST [Vol. XLI 



The skeletal structure of jNIoropus is a unique combination of 

 characters. The phalanges are highly modified, terminating in 

 cleft ungues which were, no doubt, covered by heavy claws; other- 

 wise the skeleton is distinctively of an ungulate type, most closely 

 resembling the Perissodactyla. The fore limbs are longer than 

 the hind limbs; they, together with the clawed feet, must have 

 given to the animal a very peculiar appearance. Some species 

 are as large as an African rhinoceros, or even larger. In the 

 American Naturalist, March 1889, p. 151, Professor Cope estab- 

 lished a separate order (Ancylopoda) for these different forms, 

 which in the Miocene time extended over Europe, Asia, and 

 America. After a study of the recently discovered remains, which 

 include nearly all parts of the skeleton, the present writer would 

 place Moropus as a distinct genus, in the Chalicotherioidea w^hich, 

 he is inclined to believe, should be considered as an aberrant 

 superfamily of the Perissodactyla, as it was provisionally regarded 

 by Professor Osborn^ in a recent publication. 



At this point it is thought best to give a short description of a 

 few characteristic features in the osteology of the skeleton of Moro- 

 pus as we know it from the material in the Carnegie ]\Iuseum at 

 Pittsburgh. 



The Skull 



No. 1707 Carnegie ^Museum Catalogue of Vertebrate Fossils. 



The skull, on which these brief notes are based, was found in the 

 Agate Spring Fossil Quarry by Mr. W. H. Utterback. It is that 

 of a young individual, which, when found, was disarticulated. We 

 have not, as yet, found a perfect skull of Moropus,^ but aside from 

 this our material is quite complete. The parts, associated in this 

 skull, but which may not belong to the same individual, are the 

 occipital condyle, the basioccipital (No. 1707 A), and the lower 



