ORPHEAN WARBLER. 



393 



by its much whiter throat, and by having the cheeks and the nape of the 

 same colour as the head, instead of being, as in the Blackcap, the same 

 colour as the sides of the throat. Although the Orphean Warbler is on 

 an average a larger bird than the Blackcap, the dimensions of the wing 

 and tail respectively overlap ; but the length of the bill appears to be an 

 invariable guide. In the Orphean Warbler the culmen, measured from 

 the angle of its junction with the skull, never measures less than -6 inch, 

 whilst in the Blackcap it varies from '58 to '5. A still more reliable dis- 

 tinction may be found in the colour of the outside tail-feather, which in 

 the Orphean Warbler is always white for some distance from the tip, 

 and in the Blackcap is exactly the same as the other feathers. 



There seems to be considerable difference in the intensity of the colonring 

 of the black head of the adult male of this species so much so that 

 Professor Newton, having apparently had access to too small a series of 

 skins, has arrived at the conclusion that the black head " after the 

 autumnal moult changes to dark grey." This is certainly not the case, 

 as the examples with the blackest heads I have ever seen were collected 

 by Brooks at Etawah in November ; and it seems to me probable that, in 

 addition to having a longer bill, the eastern race (S. orphea, \ar.jerdoni) 

 has also a blacker head. Examples from Asia Minor are somewhat inter- 

 mediate in this respect. 



