EXPLANATION OF THE PLATES. 125 
Figs. 6, 7. Fragment of a superior true molar. Fig. 6. Inner view. Fig. 7. Triturating surface of the 
same specimen, presenting a large conical lobe, with portion of an enamelled pit at the outer side of its 
base. 
Figs. 8-12. The size of nature. 
Figs. 8-10. A second? inferior molar of the left side. Fig. 8. The triturating surface. Fig. 9. The 
outer view. Fig. 10. The inner view, which is a vertical plane. 
Figs. 11, 12. An inferior canine tooth, the size of nature. Fig. 11. Outer view. Fig. 12. Inner view. 
PEATE Xx Vir 
All the figures of the natural size, except 8-10, which are two-thirds the diameter. 
Figs. 1-10. Titanotherium Proutti. 
Figs. 1-3. A superior premolar. Fig. 1. Inner view. Fig. 2. Outer view. Fig. 3. View of the tritu- 
rating surface. 
Fig. 4. View of the triturating surface of another superior premolar. 
Figs. 5, 6. Fragment of a superior premolar. Fig. 5. View of the triturating surface. Fig. 6. Inner 
view. 
Fig. 7. View of the triturating surface of a fragment of a superior premolar. 
Figs. 8-10. A last posterior inferior molar of the left side. Fig. 8. Outer view. Fig. 9. View of the 
triturating surface. Fig. 10. Inner view. 
Figs. 11-13. Palaeotherium gigantewm. Views of three fragments of as many superior molar teeth ; 
being single external lobes seen upon their outer face. 
PAT Br eV Pi b. 
Figures of the natural size. 
Machatrodus primaevus. 
Fig. 1. View of the right side of a skull, with the lower jaw. The symphysis of the latter, upper inci- 
sors, and zygoma are broken away. The upper jaw presents a portion of the canine, and the second to the 
last molar inclusive; and in the lower jaw the first and a portion of the second molars are visible. 
Fig. 2. Superior view of the right half of the same specimen as the preceding. 
Fig. 3. View of the left side of the lower jaw, containing the three molars and a portion of the upper 
jaw, exhibiting the second molar, from the same specimen as the preceding. 
Fig. 4. Outer view of the right inferior canine, which was attached to the mass of matrix adhering to the 
preceding specimen. 
Fig. 5. Front or anterior view of the same tooth. 
‘ PaAC Et XL EX 
Figures two-thirds the diameter of nature. 
Testudo Nebrascensis. 
Fig. 1. Dorsal view of the carapace. 
Fig. 2. Lateral view of the carapace. 
Fig. 3. Inferior view of the sternum. 
17 
