LESSER WHITETHROAT. 411 
The Lesser Whitethroat has the most extensive range of any member of 
this genus, breeding in the Palearctic region, from the Atlantic to the 
Pacific. In sucha large range it is not to be wondered at that the bird is 
subject to considerable variation. This is an excellent example of a species 
breaking up into four species. Typical examples of each present excellent 
characters, and have fairly well-defined geographical limits. Unfortu- 
nately, however, for the student who is anxious to define his species with 
greater accuracy than Nature has hitherto succeeded in accomplishing the 
task, intermediate forms occur, and individuals do not always recognize 
their geographical limits as well-behaved species ought to do. As Hume 
very justly observes, this is a case in which some ornithologists will treat 
the birds as four species, whilst others will only consider them four 
races of one somewhat variable species. I prefer to treat them as sub- 
species, adopting the provisional hypothesis that the intermediate forms are 
the result of the interbreeding of the several races where their geo- 
graphical ranges meet. 
The European or typical form of the Lesser Whitethroat breeds through- 
out Europe, Asia Minor, and Palestine, extending northwards somewhat 
beyond the arctic circle, but not quite to the limit of forest-growth. In 
South Europe it is principally known as a summer visitor; but Mr. 
Howard Saunders states that it remains during the winter in South Spain. 
It certainly winters in the southern portions of North Africa, in the oases 
of the desert, Nubia and Abyssinia, &c. 
In the valley of the Lower Volga, North Persia, Turkestan, the whole 
of Siberia up to lat. 67°, and North-east China, the Siberian form of the 
Lesser Whitethroat, S. cinerea, var. affinis, occurs in summer, wintering 
in Baluchistan, the whole of India, and Ceylon. This form only differs 
from the typical species in having the second primary intermediate in 
length between the sixth and seventh, in rare instances between the 
seventh and eighth (in the European species the second primary is inter- 
mediate in length between the fifth and sixth). It also differs very mate- 
rially in its song, apparently having forgotten or never learnt the trill 
which its European ally constantly introduces. 
In the Himalayas the Lesser Whitethroat differs from the European 
form in having the upper parts an almost uniform bluish grey, the back 
being scarcely suffused with brown at all. In its wing-formula it agrees 
with the Siberian form, but is, on an average, larger than either of the 
two forms hitherto mentioned, the length of wing varying from 2°8 to 2°55 
inch instead of from 2°65 to 2°45. Hume named this form S. althea. It 
breeds abundantly in the extreme north-west of Cashmere, and winters in 
the North-west Provinces of India. 
The fourth form of the Lesser Whitethroat, to which Hume gave the 
name of S. minuscula, is a small desert race differing from its near allies in 
