G9 



of the opposite side and several other bones of the skeleton, near the Lodge- 

 Pole Trail, crossing Dry Creek Valley. The specimen was found in part ex- 

 posed and partially imbedded in the indurated clay of a butte, in company 

 with quite a profusion of well-preserved shells of Helix wyomingensis. 



The jaw resembles in its form that of Hyrachyus agrarius, and also that 

 of the recent tapir. It contained a series of six molars, of which it retains 

 the back four. The molars are separated by a wide hiatus from a continuous 

 arch of alveoli, for the accommodation of the incisors and canines, which corres- 

 pond in number with those of the tapir. 



The depth of the jaw is rather less than in the fragments previously 

 described, while the dimensions of the molar series is nearly the same. The 

 measurements of the specimen are as follows : 



Lines. 



Length of space from incisive alveoli to back of last molar 42 



Length of space occupied by the molar series 24 



Length of space occupied by the true molars 14.J 



Anteroposterior diameter of last molar 4£ 



Length of symphysis ... 16 



Length of hiatus in advance of molars 12 



Depth of jaw below molars 9£ 



An upper-jaw fragment, recently sent to me by Dr. Carter, I suppose to 

 pertain to Hyrachyus nanus. It contains the fangs of the anterior three 

 premolars, and the entire last one, which is represented in Figs. 21, 22, Plate 

 XXVII, magnified two diameters. This premolar resembles the corresponding 

 tooth of H. agrarius, but the ridge in the latter, which represents the postero- 

 internal lobe in the true molars, is reduced to the smallest rudiment. 



The space occupied by the four premolars measures 11£ lines. The 

 breadth of the last premolar is 3.2 lines ; the width transversely is 4 lines. 



LOPHIOTHERIUM. 



LOPHIOTHEKIUM SYLVATICUM. 



The genus Lophiotlierium was proposed by Gervais, from some fragments 

 of several lower jaws with molar teeth, which were found in association with 

 remains of true Pafaeotheria, in a formation of France which he regards as 

 belonging to the upper Eocene Tertiary. The genus is viewed as a tapiroid 

 pachyderm closely allied to Lophiodon, though the molar teeth appear very 

 unlike those of the latter. 



During Professor Hayden's exploration of 1870, a specimen was found on 



