GRASSHOPPER WARBLER. 345 
‘7 inch, and in breadth from *55 to’5 mech. The number ranges from 
four to seven. 
The general colour of the upper part of this bird is olive-brown, but 
sometimes it approaches russet-brown ; each feather has an obscure dark 
centre, which becomes nearly obsolete on the sides of the neck and on the 
longest upper tail-coverts. The outer webs of the quills and tail-feathers 
are edged with olive-brown, most conspicuously so on the innermost 
secondaries. The chin and the centre of the belly are nearly white, which 
shades into buffish brown on the breast, flanks, thighs, and under tail- 
coverts, most of the latter having dark brown centres. Bill dark brown 
above, pale horn colour below; legs, feet, and claws pale brown; irides 
hazel. 
In birds of the year the whole of the underparts are more or less suffused 
with yellow, and many of the feathers of the throat and flanks have dark 
centres. A slight tinge of yellow on the underparts, and some of the 
pectoral streaks are frequently found in young birds after their first spring 
moult. 
It is very difficult to form a diagnosis which may always distinguish the 
Grasshopper Warbler from its two very near allies; but L. straminea 
appears always to have a more rounded wing than the other two. The 
second primary is always shorter than the fourth, and frequently shorter 
than the fifth ; whilst in the other two species it is sometimes equal in 
length to the third aud sometimes only to the fourth, but is never shorter 
than the fourth. L. lanceolata may usually be distinguished by having the 
general colour of the upper parts russet-brown instead of olive-brown ; 
but in a large series the most russet examples of L. locustella are un- 
distinguishable in colour from the least russet examples of L. lanceolata. 
As regards the spotting on the under surface, the breast is generally 
spotted in L. lanceolata and occasionally slightly so in the other two 
species. The flanks are spotted sometimes in L. locustella, generally in 
L. straminea, and always in L. lanceolata; whilst the under tail-coverts 
are always spotted in L. straminea, and generally so in the other two 
species, 
