96 GEOGRAPHICAL DISTRIBUTION 



species of so-called flying-lizards (Draco), animals provided with 

 a lateral expanded tegumentary membrane ; and of crocodilians, 

 the true crocodile (Crocodilus) and the gavial (Gavialis), the latter 

 restricted to the rivers of the Indian Peninsula. 



The several fauna! sub-regions, especially those of the conti- 

 nental tract, are most intimately related to one another, and do not 

 admit of sharp delimitation. Yet a number of forms, whether 

 negatively or positively, may be said to define each. Thus, among 

 the Mammalia, the lion, hyena, fox, lynx, mellivore, buffalo, nyl- 

 ghau, gazelle, and true antelope, may be said to represent distinct- 

 ive types of the first, or Indian sub-region, being absolutely restrict- 

 ed to it, or just passing beyond its confines. The Cingalese sub- 

 region is characterised, among other forms, by the loris, which it 

 alone possesses; by a peculiar genus of civet-cats (Onychogale), and 

 Platacamthornys among the mice. The fauna, especially of the 

 island of Ceylon itself, is related on the one side to that of the 

 Himalayas, and on the other to that of the Indo-Malayan sub-region, 

 differing broadly from the fauna of the central and northern por- 

 tions of the Indian Peninsula. The relationship with the Malayan 

 fauna is especially marked in the case of the Lepidoptera and Cole- 

 optera among insects, many of the more distinctive or abundantly 

 represented types belonging exclusively to the two faunas under 

 consideration. The individuality of the Cingalese reptilian and 

 amphibian faunas is well marked through the number and variety 

 of peculiar genera, which, perhaps, more than any other animals, 

 serve to characterise the sub-region. All the members of the 

 Uropeltidae, or rough-tailed burro wing -snakes, appear to be con- 

 fined to this tract. The poisonous snakes of the entire peninsula 

 of India are, according to Fayrer, comprised in eleven genera, rep- 

 resenting three families, Elapidse, Viperidse, and Crotalidre (pit- 

 vipers), and some twenty-five species. Among the more venomous 

 forms are Naja (the cobra, which ascends the Himalayas to a height 

 of eight thousand feet), Ophiophagus, and Bungarus, of the Ela- 

 pidse ; Daboia and Echis representing the vipers ; and Trimeresurus 

 belonging to the pit-vipers. In addition to the terrestrial Thanato- 

 phidia the marine-snakes (Hydrophidre), winch inhabit brackish 

 estuaries and tide-water streams, furnish an additional contingent 

 of thirty-five or more species. 



The two remaining sub-regions, the Indo-Chinese and the Indo- 



