| Henricosborniidae(noun, creature, appearance, paleocene) |
| Hesperocyoninae(noun, creature, appearance, eocene) |
| Hoanghoniinae(noun, creature, appearance, eocene) |
| Homalodotheriidae(noun, creature, appearance, eocene) |
| Horusornithidae(noun, creature, appearance, eocene) |
| Hyaenodon(noun, creature, appearance, eocene) |
| Hyaenodontidae(noun, creature, appearance, paleocene) |
| Hypertragulidae(noun, creature, appearance, eocene) |
| Hypertragulus(noun, creature, appearance, eocene) |
| Hyporhina(noun, creature, appearance, eocene) |
| Hyracodontidae(noun, creature, appearance, eocene) |
| Indricotheriinae(noun, creature, appearance, eocene) |
| Interatheriidae(noun, creature, appearance, paleocene) |
| Ischnochiton(noun, creature, appearance, eocene) |
| Isotemnidae(noun, creature, appearance, paleocene) |
| Kentriodontidae(noun, creature, appearance, oligocene) |
| Lazarussuchus(noun, creature, appearance, paleocene) |
| Leontiniidae(noun, creature, appearance, eocene) |
| Lepidopleurus(noun, creature, appearance, paleocene) |
| Leptomerycinae(noun, creature, appearance, eocene) |