COPE.] PALEONTOLOGY MIOCENE PERIOD. 495 



is an elongate crest in place of the little trochanter. The trochlear 

 groove is angular, and bounds a pit just above its proximal end 5 the 

 condyles are subequal. 



The crest of the tibia is deeply grooved, and the spine divided by a 

 ■wide gutter. The external face is concave proximally, and turns to the 

 front distally. The inner j)roximal face unites on the last third of the 

 length, to become the internal face. The distal posterior face narrows 

 upward, and runs out below the inner facet of the head. The astrag- 

 alus has the hour-glass face quite open. The inner tuberosity of the 

 head extends within the line of the trochlea a half-inch. The cuboid 

 facet is oblique and parallel to the outer margin of the head, and con- 

 stitutes one-fourth the width of the latter. 



Measurements. 



M. 



Length of radius 0.198 



Diameter of its carpal face 041 



"Width of humerus, distally 058 



Depth of outer condyle of humerus, distally .048 



Long diameter of glenoid face of scapula 042 



Short diameter of g.lenoid face of scapula 038 



Length of femur, (over all) 295 



Proximal width of femur, (over all) 100 



Diameter of head, (antero-posterior) 042 



Least transverse diameter of shaft 035 



Transverse diameter of condyles 060 



Antero-posterior diameter at condyles 0S4 



Length of tibia 230 



Diameter of head, antero-posterior 580 



Diameter of head distally, antero-posterior 036 



Diameter of head distally, transverse 060 



Diameter of head of astragalus, transverse 048 



This rhinoceros was about the size of a mule. 



AnERATHEEiUM occiDENTALE, Leidy, Ext. Fauna Dak. and Neb., p. 228, 

 Plate xxii. 



Several specimens from different localities. 



ACERATHEHIUM QUADEIPLICATUM, Cope, Syracodon quadripUcatus. 



Cope, Pal. Bull., No. 15, p. 1. 



This species is similar to the last in bulk, with greater proportional 

 elongation of the teeth of the premolar series, at least. It «is repre- 

 sented by two individuals, one possessing the permanent, the other the 

 temporary dentition, at least in part. 



The former presents only the second and third premolar teeth with 

 an alveolus of the first. The third premolar has four roots and strong 

 basal cingula fore and aft only. The transverse crests are simple and 

 separate. A strong but short crest originates from the outer marginal 

 crest between them, and being in near proximity to the anterior and trans- 

 verse, it nearly isolates a triangular valley with it. There is a low 

 tubercle between the bases of the inner extremities of the transverse 

 crests. The second premolar is three-rooted only, and is narrowed ante- 

 riorly. Its two inner cross-crests are widely separated, and the inter- 

 vening branch is rudimental. The anterior prolongation of the external 

 crest is longer than the i^osterior. 



The second specimen consists of molars in both maxillary bones, viz : 

 the four premolars, probably deciduous. They differ in appearance from 

 those above described, but not in essential details. 



The transverse crests are little curved, and the outer elevated crest 



