LIST OP ILLUSTRATIONS IN TEXT. IX 



FIG. PAGE 



45. View of grinding surface of right second lower molar of 



Elephas antiquus, from the Pleistocene of Grays, Essex . 56 



46. View of grinding surface of upper molar of Elephas meridio- 



naUs, from the Upper Pliocene of Tuscany ... 57 



47. Vertical longitudinal section of lower molar of Mastodon . 58 



48. Vertical longitudinal section of molar of Elephas (Stegodon) 



insignis, from the Lower Pliocene of the Siwalik Hills, 

 India ......... 58 



49. Vertical longitudinal section of molar of Elephas planifrons, 



from the Lower Pliocene of the Siwalik Hills ... 58 



50. View of grinding surface of lower molar of Mastodon siva- 



lensis, from the Lower Pliocene of the Siwalik Hills . 59 



51. View of grinding surface of upper molar of Elephas (Stegodon) 



cUfti, from the Lower Pliocene of the Siwalik Hills . 59 



52. View of part of grinding surface of upper molar of Elephas 



planifrons, from the Lower Pliocene of the Siwalik Hills . 59 



53. Lower molar of Mastodon americanus, from the Pleistocene 



of North America ...... 60 



54. Skeleton of Mastodon americanus, from the Pleistocene, 



Missouri, U.S.A 61 



55. Skeleton of Tetrabelodon angustidens, from the Middle 



. Miocene of Sansan, France ...... 62 



56. Left upper milk-molars of Tetrabelodon longirostris, from 



the Lower Pliocene of Eppelsheim, Hesse-Darmstadt . 62 



57. Skull and mandible of Dinotherium giganteum, from the 



Lower Pliocene of Eppelsheim ..... 63 



58. Left upper teeth of Dinotherium giganteum, from the Lower 



Pliocene of Eppelsheim ...... 63 



59. Skull and mandible of Elephas (Stegodon) ganesa, from the 



Lower Pliocene of the Siwalik Hills, India ... 64 



60. Skull and mandible of Tetrabelodon angustidens, from the 



Middle Miocene of Sansan, France. (After 0. W. Andrews) 64 



61. Skull and mandible of Palseomastodon beadnelU, from the 



Upper Eocene of the Fayum, Egypt. (After C. W. Andrews) 65 



62. Skull and mandible of Mceritheri/u/m J/yonsi, from the Middle 



Eocene of the Fayum, Egypt. (After 0. W. Andrews) . 65 



63. Teeth of Beaver (Castor fiber), from the Fens of Cambridge- 



shire . 67 



64. Skeleton of Steller's Sea-cow (Bhytina gigas), from the 



Pleistocene of Bering Island ...... 68 



65. Skeleton of Salithermm schinzi, from the Oligocene of 



Hesse-Darmstadt ........ 69 



66. Tympanic bone of Whalebone-Whale (Balsena prvmigenia), 



from the Bed Crag of Suffolk . . . . .70 



67. Skull and upper molar tooth of Zeuglodon cetoides, from 



the Eocene of Alabama, U.S.A 70 



68. Skeleton of SceUdotherium leptocephahwm, from the Pampa 



Formation of Buenos Aires, Argentine Bepublic . . 72 



69. Lower jaw of Megatherium americanum, from the Pampa 



Formation of Buenos Aires ...... 73 



70. Skeleton of Olyptodon clavipes, from the Pampa Formation 



of Buenos Aires ........ 75 



