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INDIAN REGION .Of Crocodilia C. palustris, the " mugger " or marsh crocodile, and C. porosus; Gavialis gangeticus; Tomistoma schlegeli in Borneo, Malacca and Sumatra. Of tortoises Platy-sternum megacephalum, type of a family from Siam to S. China; many Trionychidae and Testudinidae, mostly aquatic; whilst the terrestrial Testudo is very scantily represented. One species which is common in the Indian peninsula (T. stellata) is so similar to an African species as to have been considered identical with it; the Burmese tortoise is also closely allied to it, and the two others extend far into western-central Asia . Thus this type is to be considered rather an immigrant from its present headquarters, Africa, than a survivor of the Indian Tertiary fauna, which comprised the most extraordinary forms of land tortoises. Wallace's line marks the E. boundary of Trionyx; species of this genus are common in Java and Borneo, and occur likewise in the Philippine Islands, but are not found in Celebes, Amboyna or any of the other islands E. of Wallace's line. Agamidae are exceedingly numerous, and are represented chiefly by arboreal forms, e.g. Draco (q.v.) is peculiar to the region, Ceratophora and Lyriocephalus exclusively Ceylonese; terrestrial forms, like Agama and Uromastix, inhabit the hot and sandy plains in the N.W., and pass uninterruptedly into the fauna of western-central Asia and Africa. The Geckonidae, Scincidae and Varanidae are likewise well represented, but without giving a characteristic feature to the region by special modification of the leading forms except the gecko Ptychozoon homalocephalum in Malaya. The Lacertidae are represented by one characteristic genus, TachydromusOphiops and Cabrita being more developed beyond the limits assigned to this region. Finally, the Eublepharidae and Anguidae, families whose living representatives are probably the scattered remains of once widely and more generally distributed types, have retained respectively two species in W. India, and one in the Khasi Hills, whilst the presence of a single species of chameleon in S. India and Ceylon reminds us again of the relations of this part of the fauna to that of Africa.
The Indian region excels all the other tropical countries in the great variety of genuine types and numbers of species of snakes . Boulenger' recognizes 267 species, i.e. about one-fifth of the total number of snakes known. India is the only country in the world possessing viperine, crotaline and elapine poisonous snakes (their proportion to harmless snakes being about I : Io), e.g. Vipera russelli, the " daboia " (see VIPER) ; Lachesis, e.g. gramineus, an arboreal pit viper; Naja tripudians, the cobra; Bungarus coeruleus, the " krait "; Callophis; and Hydrophinae along the coasts of the whole region. Several sub-families and families are peculiar to the region: the Uropeltidae with Rhino phis in southern India, and Uropeltis confined to Ceylon; Ilysiidae in Ceylon and Malay Islands, elsewhere only in S. America; the opisthoglyphous Elachistodon westermanni of Bengal; the Homalopsinae, with many species from Bengal to N. Australia; further the Amblycephalidae; Xenopeltis unicolor, sole type of a family; and the Acrochordinae, a sub-family of aglyphous Colubridae, ranging from the Khasi Hills to New Guinea . Of other Colubridae, we notice numerous Tropidonotus, Coronella. and Zamenis, the latter one of the most characteristic types of the warmer parts of Eurasia. Tree-snakes, e.g. Dipsas and Dendrophis, are common. Of other families we note a great number of Typhlopidae, of which T. braminus occurs even on Christmas Island . Lastly various species of Python, but no Glauconiidae, the only family not represented in the Indian region, which claims the Uropeltidae, Xenopeltidae and Amblycephalidae as ppeculiar to itself.
Gunther remarks that to this region Japan has to be referred. This is clearly shown by the presence of species of Ophites,Callophis, Trimeresurus s. Lachesis, Tachydromus, characteristically Indian forms, with which species of Clemmys, Trionyx, Gecko, Halys, and some Colubrines closely allied to Chinese and Central Asiatic species are associated. Halys is a central Asiatic pit viper. The few reptiles inhabiting the northern part of Japan are probably of palaearctic origin.
End of Article: INDIAN REGION
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