THE ISLANDS OF THE BAY OF BENGAL. 127 



Yet all the missing sub-groups above enumerated are well 

 represented on the Arakau Hills, of which the whole of the- 

 islands with which we have to deal, except Narcondam and Barren 

 Islands, would seem at one time to have formed a continuation ! 

 The next most notable point is the completeness with which 

 we have passed out of the range of the Palaearctic fauna. Set- 

 ting aside waders and swimmers, (whereof the species common to 

 the islands and Europe are cosmopolites,) out of 121 species, only., 

 ten have any claims to be considered European. These are — 

 8. Falco peregrinus, Gmel., (p. 140.) 



54. Circus geruginosus, Lin., (p. 150.) 



82. Hirundo rustica, Lin., (p. 154.) 



851. Cyanocincla cyana, Lin., (p. 220.) 



483. Pratincola rubicola, Lin., (p. 2-33.) 



539. Cisticola schcenicola, Bonap., (p. 235.) 



592. Calobates boarula, Penn., (p. 237.) 



593 ter. Budytes cinereocapilla, SavL, (p. 237.) 

 593 quat. „ flava, Lin., (p. 238.) 



599. Corydalla Richardi, Vieill, (p. 239.) 



Even of these it will be observed that many are, by some 

 ornithologists, considered distinct, and entitled to specific separa- 

 tion from the European forms, of which according to the views, 

 of these naturalists these Asiatic races are representatives. 



Thus the first species on the list is separated, as F. calidus, 

 Lath ; the third as H. gutturalis, Scop ; the fourth as C. Pandoo, 

 Sykes ; the fifth as P. indica, Bly th ; and the 7th as C. melanope, 

 Pallas ; and though I cannot myself concur in the necessity or 

 expediency of giving specific rank to the races that these 

 appellations are intended to designate, I quite admit that in 

 most or many of the individuals that compose them, (though not 

 in all and that is the crucial test,) a certain degree of variation 

 from the European type is observable. 



The next point is the highly specialized character of the 

 Avifauna. Excluding waders and swimmers we have 117 well- 

 ascertained species, out of which no less than 43 . or more than 

 one-third are peculiar to the islands ; two or three of the six 

 imperfectly identified species are probably also peculiar to the 

 islands, while twelve more, if not distinct species, (as many of 

 them will certainly be considered by some ornithologists,) are, at 

 any rate, very recognizably distinct races. So that of the 

 Raptores, Insessores, Gemitores and Rasores, known to occur 

 in the islands, nearly one-half are peculiar to these. 



So much difference, of opinion exists as to the specific value of 

 forms, that I feel it necessary to enumerate the several species 



