HOLLAND AND PETERSON: OSTHOLOGY OF THE CHALICOTHEROIDEA. 219 
The specimen very probably does not represent a Chalicotheroid, as an ex- 
amination of its dentition shows. 
Sphenocelus uintensis OSBoRN, Bulletin American Museum Natural History, Vol. 
VII, p. 98 (1895). (Cf. supra under Sphenocelus, p. 215.) 
CHAPTER IV. THE SPECIES OF THE GENUS MOROPUS. 
Order UNGULATA Ray. 
Suborder PERISSODACTYLA Owen. 
Superfamily CHALICOTHEROIDEA Gill. 
Family CHALICOTHERIIDA Gill. 
Genus Moropus Marsh. 
1. M. oregonensis (Leidy). 
(Lophiodon oregonensis) ‘Contributions to the Extinct Vertebrate Fauna of the 
Western Territories,” p. 219, Pl. II, Fig. 1 (1870). 
Type: Fragment of maxillary containing two cheek-teeth (P* M’) (see Fig. 5, 1-2). 
Location of Type: Condon Collection (fide Leidy); Peabody Museum, Yale Uni- 
versity, No. 10030. (Purchased from Dr. Condon by Professor Marsh.) 
Geological Horizon: Bridge Creek Beds, John Day region, Oregon (Lower Mio- 
cene?). 
The description and figure given by Leidy (I. c.) were decided by Mr. Peterson 
to represent the dentition of a Chalicotheroid referable to Moropus. Quite re- 
cently, as this paper was going to the press, through the kindness of Dr. R. 8. Lull 
we have received for purposes of study and comparison a number of fragments 
preserved in the Peabody Museum. It was intensely gratifying to discover in 
this material the type of Leidy’s Lophiodon oregonensis, and associated with this 
by Professor Marsh are two premolars and a molar which may well have pertained 
to the same individual as Leidy’s type, judging from the similarity in size and 
wear, together with the coloration and general condition of the different fragments. 
The fragments pretty plainly show that they are surface fragments, and may 
have been picked up at the same spot by different parties at different times. A 
first and second upper molar also referred by number to the same specimen, belong, 
however, undoubtedly to a different individual, and are here designated by No. 
10030a, in order to separate them from Leidy’s type. Besides these specimens 
coming from the Yale Museum, we have received from the American Museum of 
Natural History a posterior upper molar from the John Day formation. This 
