REFERENCES TO THE PLATES. 465 



Fig. 27. Molar of til e right side, probably the fourth. Length 18 lines; breadth above IO2 lines, 

 below 8 lines; thickness above 41 lines, below 5 lines. 



Fig. 28. A series of the anterior three molars of the right side. Length of third molar 20 lines: 

 breadth above 11 lines, below 9 lines; thickness above 5 lines, below 6 lines. 



Fig. 29. Second or third molar of the left side. From the jMauvaises Terres of White River. 



Fig. 30. Intermediate molar, probably the third of the left side. Length 2 inches; breadth above 

 1 inch, below 9i lines; thickness above 6 lines, below G lines. 



Fig. 31. Intermediate molar, probably the third of the leftside. Length 20 line.s ; breadth above 11 

 lines, below 10 lines ; thickness above 5 lines. 



Fig. 32. An intermediate molar, probably the third of the right side. The specimen is contained in 

 a fragment of the jaw, and is about half worn away. The breadth of its triturating surface is 1 inch ; 

 its thickne.ss, independent of the cement, 7 lines, with the latter 8 lines. 



Fig. 33. An intermediate molar of the left side, about half worn down. Length 14 lines ; breadth 

 at triturating .surface 13 lines ; thickness 7 lines. 



Fig. 34. An intermediate molar of the right side, moderately worn. Length 22 lines ; breadth above 

 13} lines, below 9 lines. 



Fig. 35. An intermediate molar of the right side. Length 22 lines; breadth above 14 lines, below 

 10 lines; thickness above 5 lines, below 6 lines. 



Fig. 36. An intermediate molar of the left side. Length 22 lines ; breadth 11 lines. 



Fig. 37. Second temporary molar of the right side. Length at central axis 11 lines; breadth of tri- 

 turating surface 13} lines. 



Fig. 38. Third temporary molar of the left side. Breadth of masticating surface 13} lines. Sj^eci- 

 men contained in a fragment of the jaw. 



Fig. 39. Posterior two molars of the right side of Eqnus excchus. 



Fig. 40. An intermediate molar of the right side. Breadth of triturating surface 1 inch ; thickness 

 4J lines. 



Fig. 41. Second and third temporary molars of the left side. The specimens are contained together 

 in a fragment of the jaw. 



PLATE XX. 



Anchitheeium Baiedi. See page 303. 

 Of the natural size. 



Fig. 1. View of the left side of a skull, containing in both jaws all the molar teeth except the small 

 anterior first lower premolar. 

 Fig. 2. Upper view of the skull, from the same specimen. 



PLATE XXI. 



All the figures are of the natural size except 14, 15, 16, 18, 19. 

 Figs. 1-6. Htopotamus ameeicanus. See page 202. 



Fig. 1. Upper true molars of the left side, viewed on their triturating surfaces, a, h, c, first, second 

 and third. 



Fig. 2. Outer view of the posterior pair of the series, h, second, c, third molar. 

 Fig. 3. Second and third premolars of the left side, viewed on their triturating surfaces. 

 Fig. 4. Outer view of the same teeth, contained in a fragment of the jaw. 



59 



