| [a]Hyostylic.] | [a]Autostylic.] |
| Subclass 1. Elasmobranchii. | Subclass 3. Holocephali. |
| 1. Ichthyotomi. | 1. (unknown). |
| 2. Selachii. | 2. Chimaeroidei. |
| 3. Acanthodii. | 3. (unknown). |
| Subclass 2. Teleostomi. | Subclass 4. Dipnoi. |
| 1. Crossopterygii (Palaeozoic | 1. Sirenoidei. |
| and Mesozoic). | |
| 2. Crossopterygii (Cainozoic). | 2. (unknown). |
| 3. Actinopterygii. | 3. Arthrodira. |
CLASS II. AMPHIBIA.
- Order 1. Urodela.
- Suborder (1). Ichthyoidea.
- Group A. ,Perennibranchiata.
- Family Menobranchidae. Menobranchus.
- Family Proteidae. Proteus—olm.
- Family Sirenidae. Siren.
- Group B. Derotremata.
- Family Amphiumidae. Megalobatrachus.
- Cryptobranchus (Menopoma).
- Amphiuma.
- Suborder (2). Salamandrina.
- Family Salamandridae. Salamandra—salamander.
- Molge—newt.
- Onychodactylus.
- Amblystoma.
- (Siredon—axolotl, larval Amblystoma).
- Batrachoseps.
- Spelerpes (Gyrinophilus).
- Order 2. Labyrinthodontia.
- Group Lepospondyli. Branchiosaurus.
- Group Temnospondyli. Archegosaurus.
- Nyrania.
- Euchirosaurus.
- Group Stereospondyli. Capitosaurus.
- Mastodonsaurus.
- Order 3.Gymnophiona.
- Family Caeciliidae. Siphonops.
- Epicrium.
- Order 4. Anura.
- Suborder (1). Aglossa.
- Family Xenopidae. Xenopus.
- Family Pipidae. Pipa—Surinam toad.
- Suborder (2). Phaneroglossa.
- Group Arcifera.
- Family Discoglossidae. Discoglossus—painted frog.
- Bombinator—fire-bellied frog.
- Alytes—midwife frog.
- Family Pelobatidae. Pelobates—toad frog.
- Family Hylidae. Hyla—green tree-frog.
- Family Bufonidae. Bufo—toad.
- Docidophryne.
- Family Cystignathidae. Ceratophrys—horned frog.
- Group Firmisternia.
- Family Ranidae. Rana—common and edible frogs.
- Family Engystomatidae. Brachycephalus.
B. SAUROPSIDA.
CLASS I. REPTILIA[16].
- Order 1. Theromorpha.
- Group Anomodontia. Dicynodon.
- Udenodon.
- Group Placodontia. Placodus.
- Group Pariasauria. Pariasaurus.
- Elginia.
- Group Theriodontia. Dimetrodon.
- Galesaurus.
- Cynognathus.