ORPHEAN WARBLER. 393 
by its much whiter throat, and by having the checks and the nape of the 
same colour as the head, instead of being, as in the Blackeap, 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 colouring 
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, var. jerdoni) 
has also a blacker head. Examples from Asia Minor are somewhat inter- 
mediate in this respect. 
