2. Eastern Palaearctic.–Amphiumidae (Cryptobranchus); Salamandrinae (Triton, Pachytriton,* Tylototriton*); Amblystomatinae.–Bombinator, Bufo, Hyla arborea, Rana, Rhacophorus.
3. Nearctic.–Amphiumidae (Cryptobranchus, Amphiuma*); Proteidae (Typhlomolge,* Necturus*); Sirenidae*; Amblystomatinae; most Plethodontinae; Desmognathinae.*–Discoglossidae, Pelobatidae (Scaphiopus*); Bufo; Hylidae (Hyla, Acris, Chorophilus); Rana.
II. Palaeotropical region.–Characterised by the presence of Apoda and by the great prevalence of Firmisternal Anura, which amount to nearly 90 per cent of the total population. Absence of Urodela (except Amblystoma persimile*), of Cystignathidae, and practically of the Hylidae, only two of which occur in the Himalayan district. But this great chain of mountains should not be included within the region, while the outlying spurs in Upper Burma (with Amblystoma) are debatable ground. The subdivision of this widely extended region is beset with difficulties, chiefly on account of Madagascar and Papuasia. The fauna of Madagascar is very remarkable. All its Amphibia are Firmisternal, a mixture of African and Indian forms. The island agrees with Africa, in opposition to the Oriental countries, in no special point; all the Raninae, except Megalixalus, Rappia, and two rather common species of Rana, belong to different genera. Madagascar differs from Africa by the absence of Apoda, of Aglossa, and Bufonidae. On the other hand, it agrees with India or with the Malay islands, in opposition to Africa, by the possession of Dyscophinae, of the Ranine genus Rhacophorus, and the Engystomatine genus Calophrynus.
Africa and India agree with each other, and differ from Madagascar by the possession of Apoda, the genera Bufo and Nectophryne, and by the close resemblance of several genera of Raninae.
India, the Malay islands, and Papuasia with Melanesia possess Pelobatidae (Leptobrachium,* Batrachopsis,* Asterophrys*), and thereby differ considerably from Africa and Madagascar. Batrachylodes* of the Solomon Islands has unmistakable affinities with Phrynoderma* of Karen, between Burma and Siam; Oreobatrachus* of Borneo much resembles Phrynobatrachus* of West Africa; and Cornufer, typical of the Malay and Melanesian islands, occurs also in West Africa. All these Raninae indicate that the Austro-Malayan and Melanesian islands belong to the Palaeotropical region. Ceratobatrachus,* type of a sub-family, is peculiar to Melanesia.
There are consequently several possible modes of subdivision, all with a different result, according to the group of Amphibia, which we may select as of leading importance, e.g. Apoda or Pelobatidae, or Dyscophinae and Rhacophorus. The Engystomatinae and Raninae are to be eliminated, since they occur in all the countries in question. We have either to leave the whole region undivided–and it is a significant fact that the Indian countries possess not one sub-family of their own–or we must break it up into four provinces, not sub-regions:–
1. Ethiopian, or continental African, with Aglossa and Apoda, no Pelobatidae, no Dyscophinae, few Bufonidae, and many Raninae.
2. Indian and Malayan, with Apoda, no Aglossa, but with Pelobatidae, Dyscophinae, many Bufonidae and Raninae, amongst which Rhacophorus.
3. Malagasy, without either Apoda or Aglossa; with Firmisternal Anura only, chiefly Dyscophinae, and Rhacophorus and other Raninae.
4. Papuasian, without Apoda, Aglossa, Dyscophinae, and Bufonidae, but with Pelobatidae and Ranidae.