PLATE VI. 



Figs. 26, 27. Paramys deucatior : 



Fig. 26. Left side lower jaw, with the second molar, natural size. Grizzly Buttes. Dr. 

 Carter. Fig. 27. Triturating surface of the second molar, magnified three diameters. 



Figs. 28, 29. Paramys delicatissimus : 



Fig. 28. Right side of lower jaw, with all the molars, natural size. Grizzly Buttes. Dr. 

 Carter. Fig. 29. Triturating surfaces of the molar series, magnified three diameters. 



Fig. 30. Sciuravus(?) Triturating surface of a lower left third molar, magnified eight diameters. From 

 a portion of the lower jaw obtained at Grizzly Buttes by Dr. Carter. 



Figs. 31, 32. Mysops minimus : 



Fig. 31. Right side of lower jaw, with third and fourth molars, magnified two diameters. 

 Fig. 32. Triturating surfaces of the teeth, magnified eight diameters. Dr. Carter. 



FigS. 33-35. LOPHIOTHERIUM SYLVATICUM : 



Fig. 33. Portion of left side of lower jaw, with last premolar and first and last molars, 

 natural size. Fig. 34. Triturating surfaces of the last premolar and first molar. Fig. 35. 

 Triturating surface of the last molar. Specimen from Henry's Fork of Green River. 



Figs. 36, 37. Notharctus tenebrosus : 



Fig. 36. Right side of lower jaw, with canine and all the molar series except the first pre- 

 molar, natural size. Fig. 37. The triturating surfaces of the molars, magnified two 

 diameters. Specimen from Black's Fork of Green River. 



Figs. 38,39. Hipposyus fomosus(?) 



Fig. 38. Triturating surface of a lower right second molar, magnified two diameters. From 



a jaw-fragment from near Fort Bridger. Dr. Carter. 

 Fig. 39. Triturating surface of a left lower first molar, magnified two diameters. From a 

 jaw-fragment obtained by Dr. Carter near Fort Bridger. 



Fig. 40. Hipposyus robustior : 



Triturating surface of a left lower second molar, magnified two diameters. From Henry's 

 Fork of Green River. Professor Hayden. 



Fig. 41. Hipposyus formosus : 



Triturating surfaces of the upper left first and second molars, magnified three diameters 

 Specimen from near Fort Bridger. Dr. Carter. 



Fig. 42. Hyrachyus nanus : * 



Triturating surfaces of the back two premolars, and the molars, magnified one and a half 

 diameters. Taken from the left side of the lower jaw of the same specimen represented 

 in Fig. 14, of Plate II. Specimen obtained by Dr. Corson at Grizzly Buttes. 



Fig. 43. Trogosus vetulus, probably AncMppodus : 



Right lower incisor, natural size. From near Fort Bridger. Dr. Carter. 



Fig. 44. Sinopa rapax:_ 



Portion of left side of lower jaw, with last premolar and first molar, natural size. From 

 . Grizzly Buttes. Dr. Carter. 



Fig. 45. Sinopa eximia : 



Portion of left side of the lower jaw, supposed to belong to a smaller species of the former, 

 natural size. From Grizzly Buttes. Dr. Carter. 



Fig. 46. PALiEACODON VERUS : 



Penultimate molar of the upper left side, magnified four diameters. From Lodge-pole trail. 

 Dr. Carter. 



