| General Distribution. | |||||
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| Neotropical Sub-regions. | Nearctic Sub-regions. | Palæarctic Sub-regions. | Ethiopian Sub-regions. | Oriental Sub-regions. | Australian Sub-regions. |
| 1. 2. 3. 4 | 1. 2. 3. 4 | 1. 2. 3. 4 | 1. 2. 3. 4 | 1. 2. 3. 4 | 1. 2 — — |
The Ranidæ, or true Frogs, are characterised by having simple undilated toes, but neither neck-glands nor dilated sacrum. They are almost cosmopolitan, extending to the extreme north and south from the North Cape to Patagonia, and they are equally at home in the tropics. They are perhaps most abundant in South America, where a large number of the genera and species are found; the Ethiopian region comes next, while they are rather less abundant in the Oriental and Australian regions; the Nearctic region has much less (about 12 species), while the Palæarctic has only five, and these two northern regions only possess the single genus Rana. The genera are distributed as follows:—
Rana (60 sp.), ranges all over the world, except Australia and South America, although it extends into New Guinea and into Mexico and Central America; it is most abundant in Africa. Pyxicephalus (7 sp.), extends over the whole Ethiopian region, Hindostan, the Himalayas, and Japan; Cystignathus (22 sp.), is mainly Neotropical, but has three species Ethiopian. All the other genera are confined to single regions. The Neotropical genera are:—Odontophrynus (1 sp.), Pseudis (1 sp.), Pithecopsis (1 sp.), Ensophleus (1 sp.), Limnocharis (1 sp.), Hemiphractus (1 sp.), all Tropical South American east of Andes; Ceratophrys (5 sp.), Panama to La Plata; Cycloramphus (1 sp.), West Ecuador and Chili; Pleurodema (6 sp.), Venezuela to Patagonia; Leiuperus (12 sp.), Mexico and St. Domingo to Patagonia; Hylorhina (1 sp.), Chiloe. The Australian genera are:—Myxophyes (1 sp.), Queensland; Platyplectrum (2 sp.), Queensland and West Australia; Neobatrachus (1 sp.), South Australia; Limnodynastes (7 sp.), and Crinia (11 sp.), Australia and Tasmania. The Oriental genera are:—Dicroglossus (1 sp.), Western Himalayas; Oxyglossus (2 sp.), Siam to Java, Philippines and China; Hoplobatrachus (1 sp.), Ceylon; Phrynoglossus (1 sp.), Siam. The Ethiopian genera are:—Phrynobatrachus (1 sp.), Stenorhynchus (1 sp.), both from Natal.
Family 20.—DISCOGLOSSIDÆ, (14 Genera, 18 Species.)
| General Distribution. | |||||
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| Neotropical Sub-regions. | Nearctic Sub-regions. | Palæarctic Sub-regions. | Ethiopian Sub-regions. | Oriental Sub-regions. | Australian Sub-regions. |
| 1. 2 — — | — — — — | 1. 2. 3. 4 | — 2. 3 — | — 2. 3. 4 | 1. 2 — — |
The Discoglossidæ, or Frogs with a dilated sacrum, are remarkable for the number of generic forms scattered over a large part of the globe, being only absent from the Nearctic and the northern half of the Neotropical regions, and also from Hindostan and East Africa. The genera are:—
Chiroleptes (4 sp.), Australia; Calyplocephalus (1 sp.), allied to the preceding, from Chili; Cryptotis (1 sp.), Australia; Asterophys (2 sp.), New Guinea and Aru Islands; Xenophrys (1 sp.), Eastern Himalayas; Megalophrys (2 sp.), Ceylon and the Malay Islands; Nannophrys (1 sp.), Ceylon; Pelodytes (1 sp.), France only; Leptobrachium (1 sp.), Java; Discoglossus (1 sp.), Vienna to Algiers; Laprissa (1 sp.), Latonia (1 sp.), Palæarctic region; Arthroleptis (2 sp.), West Africa and the Cape; Grypiscus (1 sp.), South Brazil.
Family 21.—PIPIDÆ. (1 Genus, 1 Species.)
| General Distribution. | |||||
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| Neotropical Sub-regions. | Nearctic Sub-regions. | Palæarctic Sub-regions. | Ethiopian Sub-regions. | Oriental Sub-regions. | Australian Sub-regions. |
| — 2 — — | — — — — | — — — — | — — — — | — — — — | — — — — |
The Pipidæ are toads without a tongue or maxillary teeth, and with enormously dilated sacrum. The only species of Pipa is a native of Guiana.