Peterson: Material Discovered in Uinta Basin. 109 



From the remains of the radius and ulna it is at once evident that 

 this animal had the lower fore limb proportionally much longer than 

 the tapir, while the articulating surface for the humerus is quite 

 similar. 



The carpus is represented only by the anterior portion of the mag- 

 num, which bears a striking resemblance to the corresponding portion 

 in the recent tapir. The facet for the scaphoid rises gently in the 

 ulnar direction to form an acute angle with the nearly vertical facet 

 for the lunar and unciform on the ulnar face. The lunar facet does 

 not appear to be interrupted by a sulcus before reaching the elevated 

 posterior portion, as in the tapir, but is continuous from the dorsal 

 face backwards. The superior and inferior facets for the trapezoid 

 are not as well separated as in the tapir. In the tapir there is a deeply 

 excavated area on the radial face of the magnum which distinctly 

 separates these two facets. The facet for Mc. II is plainly represented 

 on the lower radial angle just as in the recent genus. 



On comparing the magnum with the illustration of Isectolophus 

 annectens by Osborn {I.e., p. 522, PI. X, Fig. 3) there appears to be a 

 difference in the angle of the articulations for the scaphoid, the lunar, 

 and the unciform. In Isectolophus the scaphoid articulation on the 

 magnum rises more, and in the lunar and unciform less, steeply than 

 in Helaletes. This may or may not be due to faulty drawing. 



The heads of metacarpals III, IV, and V are preserved and here 

 again there is a similarity to the corresponding portions of the tapir. 

 Mc. Ill was apparently enlarged in an equal ratio with that in the 

 recent genus. The only points of difference, capable of comparison 

 between the two, are the suddenly interrupted facet for the unciform 

 on the head of Mc. Ill, and the two separate facets for the same bone 

 (unciform) on Mc. IV in Helaletes, whereas in the tapir the facet on 

 Mc. Ill, is more continuous and the one on Mc. IV is solidly united. 

 The antero-posterior diameter of the shaft of Mc. Ill appears to be 

 relatively greater in Helaletes than in Isectolophus. Mc. IV has 

 facets on the radial angle of the head corresponding to those described 

 on the ulnar angle of Mc. III. 



M EASUREMENTS. 



Greatest antero-posterior diameter of glenoid cavity of scapula 21 mm. 



Greatest transverse diameter of glenoid cavity of scapula 17 



Greatest transverse diameter of distal end of humerus 23 



Greatest antero-posterior diameter of distal end of humerus 20 " 



