PALLAS'S LOCUSTELLE. 103 



S. certhiola lias, according to Temminck, 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 which my 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 species 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 ornithology will be much increased, and 

 our boundary species placed 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 afford a remarkable 



