Order—CETACEA.
| Fam. (Carus). | Fam. (Gray). | ||||
| Sub-order I.— Mystaceti. |  | Balænidæ | 36. | Balænidæ. | |
| Balænopteridæ | 37. | Balænopteridæ. | |||
| Sub-order II.— Odontoceti. |  | Catodontidæ | 38. | Catodontidæ. | |
| Hyperoodontidæ | 39. |  | Hyperoodontidæ. | ||
| Epiodontidæ. | |||||
| Xiphiadæ. | |||||
| Monodontidæ | 40. | (Part of Delphinidæ.) | |||
| Delphinidæ | 41. |  | Platanistidæ. | ||
| Iniadæ. | |||||
| Delphinidæ. | |||||
| Globiocephalidæ. | |||||
| Orcadæ. | |||||
| Belugidæ. | |||||
| Pontoporiadæ. | |||||
| Extinct family | Zeuglodontidæ. | ||||
Order—SIRENIA.
The order Sirenia, comprising the sea-cows, consists of a single family:
Family 42. Manatidæ.
The extensive order Ungulata comprises the three orders Pachydermata, Solidungula, and Ruminantia of the older naturalists. The following classification is that now generally adopted, the only difference of opinion being as to whether some of the groups should be classed as families or sub-families, a matter of little importance for our purpose:
Order—UNGULATA.
| Fam. | |||||
| Perissodactyla or Odd-toed Ungulates |  | 43. Equidæ | Horses. | ||
| 44. Tapiridæ | Tapirs. | ||||
| 45. Rhinocerotidæ | Rhinoceros. | ||||
| Artiodactyla or Even-toed Ungulates | | Suina | | 46. Hippopotamidæ | Hippopotamus. |
| 47. Suidæ | Swine. | ||||
| Tylopoda | 48. Camelidæ | Camels. | |||
| Tragulina | 49. Tragulidæ | Chevrotains. | |||
| Pecora | | 50. Cervidæ | Deer. | ||
| 51. Camelopardidæ | Giraffes. | ||||
| 52. Bovidæ | Cattle, Sheep, Antelopes, &c. | ||||
The two next orders consist of but a single family each, viz.:
| Order | Fam. | |
| PROBOSCIDEA | 53. Elephantidæ | Elephants. |
| HYRACOIDEA | 54. Hyracidæ | Rock-rabbits. |