326 ZOOLOGICAL GEOGRAPHY. [part hi. 



problem admittedly depends. It will, perhaps, be said that a 

 great many of the 88 genera above given are very scarce and very 

 local ; but this is certainly not the case with the majority of them ; 

 and even where it is so, that does not in any degree affect their 

 value as indicating zoo-geographical affinities. It is the pre- 

 sence of a type in a region, not its abundance or scarcity, that is 

 the important fact ; and when we have to do, as we have here, 

 with many groups whose habits and mode of life necessarily 

 seclude them from observation, their supposed scarcity may not 

 even be a fact. 



Reptiles and Amphibia. — Pieptiles entirely agree with Mam- 

 malia and Birds in the main features of their distribution. 

 Out of 17 families of snakes inhabiting Hindostan, 16 range 

 over the greater part of the entire region, and only two can 

 be supposed to show any Ethiopian affinity. These are the 

 Psammophidre and Erycidee, both desert-haunting groups, and 

 almost as much South Palsearctic as African. The genus Tro- 

 pidococcyx is peculiar to the sub-region, and Aspidura, Passerita 

 and Cynopliis to the peninsula and Ceylon ; while a large number 

 of the most characteristic genera, as Dipsas, Simotes, Bungarus, 

 Naja, Trimeresurus, Lycodon and Python, are characteristically 

 Oriental. 



Of the six families of lizards all have a wide range The 

 genera Eumeces, Pentadactylus, Gecko, Eublepharis, and Draco, are 

 characteristically or wholly Oriental ; Ophiops and Uromastix 

 are Palrearctic ; while Cliammlcon is the solitary case of decided 

 Ethiopian affinity. 



Of the Amphibia not a single family exhibits special Ethiopian 

 affinities. 



II. Sub-region of Ceylon and South-India. 



The Island of Ceylon is characterised by such striking pecu- 

 liarities in its animal productions, as to render necessary its 

 separation from the peninsula of India as a sub-region ; but it 

 is found that most of these special features extend to the Neil- 

 gherries and the whole southern mountainous portion of India, 

 and that the two must be united in any zoo-geographical pro- 



