Mr. W. T. Blauford on Indian Owls. 5.25 



by Dr. Sharpe in the Catalogue of Birds (vol. ii. 1875), 

 and roost of the identifications have been clearly shown 

 to be inevitable by Mr. Hume, for the supposed specific 

 distinctions in many cases depend merely on a more or less 

 rufous tint of the plumage, and this again, as Mr. Hume has 

 also shown {e.g. 'Stray Feathers,' vol. ix. pp. 37, 41), is 

 dependent on climate. As a rule. Owls living in damper 

 regions are more rufous, those in drier tracts greyer. It may 

 be remarked that a somewhat similar variation is found in the 

 Caprimulgi. But the matter is by no means quite so simple 

 as at first sight it may seem, for, as I shall presently show, 

 there is a particular rufous phase, in one species at all events, 

 that can scarcely be attributed to climate alone. 



There is also another and very important form of variation 

 which may, so far as India, Ceylon, and Burma are con- 

 cerned, be expressed in the formula that northern birds are 

 larger than southern. Birds from the Sub-Himalayan tracts 

 are usually largest, those from Northern and Central India 

 and from Northern Burma next, whilst a further diminution 

 is found in the extreme south of India, in Ceylon, and in the 

 Malay Peninsula. Sometimes, too, as in the case of Ninox 

 affinis, a peculiarly small race inhabits the Andaman and 

 Nicobar Islands ; and in this particular instance the smallest 

 birds are from the Audamans, which are, of course, north of 

 the Nicobars. It should be added, that this difference of size 

 is not confined to Owls, nor even to birds ; it is equally well 

 marked in several other animals, and it has been especially 

 noticed by Mr. Hampson amongst the moths. 



Strix deroepstorffi, is known by a single small tawny speci- 

 men from the Audamans. All the points of difference 

 between this Andaman bird and the ordinary Indian race of 

 S. flammea {S. javanica) are repeated in other insular races. 

 Syrnium newarense is the large Himalayan form, ^S^. indrani 

 the smaller race from the Indian Peninsula and Ceylon. As 

 a rule, the southern birds have an ochreous, the Himalayan 

 specimens a whitish disk, but the difference is not constant. 

 Not only are Assamese and Burmese birds intermediate, 

 but, as Davison has shown {' Stray Feathers,' vol. x. p. 342), 



SER. Vr. VOL. VI. 2 o 



