of the Chif chaff and Willoio- Warbler. 309 



termed an " incipient variety '' *, an aggregate of individuals 

 at the present day indistinguishable in form (colour and 

 external characteristics), but possessing a habit so different 

 from that of its type-species as to indicate a tendency 

 towards variation in form, which may in time attain that 

 first recognisable degree defined as "racial" or ''sub- 

 specific," as has presumably been the case with the Canariau 

 race of Chiffchaff'. 



As remarked before, it is either implied or stated in most 

 of the standard works of reference that the Chiff*chaff is 

 more or less resident in southern Europe. Since no records 

 for individual birds seem ever to have been attempted, it is 

 presumed this only means that the species is to be found 

 there, both in winter and summer, which is, of course, a very 

 different thing to the individuals of the species being non- 

 migratory ; I can find no real facts about that, but it is 

 important in its bearing on the present subject. 



With the view of enquiring generally into the Chiff'chaff^s 

 (P. c. colly bita) southern breeding and northern winter 

 limits, and whether any reason, geographical or physical, 

 could be deduced to account for them, I started plotting 

 out on a chart, both for the Chiffchaff and the Willow- 

 Warbler (whose strong resemblance complicates. field-obser- 

 vation on its congener), all the records I could find from a 

 fairly wide selection of references f, but soon found that the 



* Darwin (' Origin of Species ' p. 76) " . . . . varieties wliicla I have 

 called incipient species . . . . " 



Note. — I trust this will not be construed into a proposal for some new 

 sort of " Name." Naturally, such an idea would be almost as absurd as 

 to suggest giving every single bird a name of its own because it possesses 

 " individuality" and a tendency to vary, — H. L. 



t Hartert's ' Vog. palaarkt. Fauna.' H. Saunders, Man. Brit. Birds. 

 Hand-list Brit. Birds (Ilartert, Witherby, and others). Cat. Birds Brit. 

 Mus. Ibis. Eliot Howard's 'Warblers.' Irby's Ornith. Str. Gib. 

 Jourdain's ' European Eggs.' Whitaker's ' Birds of Tunisia.' 



There are doubtless other works that would offer a few more data, 

 but I cannot foresee any approach to their contributing sufficient material 

 for the original purpose, and only hope these remarks may bring out 

 some new facts not already' recorded or that have escaped my search 

 among the above. 



