Pallas’s locustelle. 
108 
S. certhiola has, according to Temininck, whose des- 
cription I follow, all the upper parts of a uniform olive, 
shaded with brown and varied by ovoid spots of blackish 
brown; these spots occupy the middle of each feather; 
the throat, front of neck, and middle of the belly pure 
white; under the throat is a zone of very small ovoid 
spots of dark brown; flanks, abdomen, and inferior tail 
coverts of a bright russet, the last-named tipped by pure 
white; tail long, wide, and much sloped. The quills are 
blackish below, and all terminated by a large mark of 
whitish ash-colour; but above there is only a small point 
of the quills in which this ashy mark is perceptible. 
The female has the colours less marked and pure. 
Figured by Gould, pi. 105, from wTich ray drawing 
is by permission taken. 
With this bird I close my list of the European species 
of the genus Sylvia of Latham. The progress of orni- 
thological discovery in modern days, however, renders 
it probable that the number will be considerably in- 
creased, as every single well-authenticated case of the 
capture of a bird within the European limits is held 
sufficient to constitute it a European speeies by modern 
writers. I hope to see this system some day altered by 
the multiplication of such excellent memoirs as those of 
Tristram and Salvin in the Ibis, by which our knowledge 
of geographical oinithology will be much increased, and 
our boundary species plaeed in their respective habitats. 
It must at the same time be borne in mind as our 
geographical divisions are entirely arbitrary, so is it 
impossible to draw a distinct line between the species 
of one quarter of the globe and another, and yet the 
faunae are sufficiently distinct to aflbrd a remarkable 
