The Tennessee Warbler 



With these rough generalizations in mind by way of guidance, it 

 must be remembered always that neither warblers nor any other birds ever 

 actually invaded a country en masse, and that each species, therefore, has 

 a perfectly independent history of its own. And it goes without saying 

 that the history of the species is simply the combined record of individual 

 birds, birds which, precisely in so far as they are individual, make history. 



A few individuals, a score perhaps, of the species Mniotilta varia have 

 gone far toward making Mniotiltine history, in that they have allowed 

 themselves to be taken within the limits of California. These occur- 

 rences serve to remind us that those eastern species which, in their age- 

 long northwesterly gropings, have reached, or nearly reached, the eastern 

 base of the Rocky Mountains, are likely to send down scouts, pioneers, 

 accidentals, waifs — call them what you will — in search of a nearer passage 

 to Panama than that afforded by the ancestral route. So far as the 

 individual is concerned, these aberrations may represent any one of sev- 

 eral happy (or unhappy) accidents: local associations with western 

 migrants upon the breeding grounds ; the failure of the migratory instinct ; 

 the superiority of the general sense of direction over the urge of the ances- 

 tral memory; — however it may come to pass, the economical purposes of 

 nature will be subserved, and we shall see more and more of these north- 

 western-reared "eastern" birds taking the short cut to Mexico, precisely as 

 their remote ancestors did across the, till then, forbidden "Great Plains." 



There have been, I believe, increasingly frequent repetitions of 

 Black-and-white Warbler records of late, so that it is, perhaps, not too 

 much to say that this species has become the commonest of the so-called 

 "accidentals." We may look forward with some degree of confidence to 

 seeing it establish itself as a regular migrant. 



No. 78 



Tennessee Warbler 



A. O. U. No. 647. Vermivora peregrina (Wilson). 



Description. — Adult male in spring and summer: Pileum and hind-neck, 

 broadly, bluish ash (deep grayish olive), faintly glanced with warbler green; remaining 

 upperparts bright warbler green; flight-feathers and tail dusky, the primaries narrowly 

 edged with whitish, a whitish blotch (or not) on tip of inner web of outermost pair 

 of rectrices; an obscure superciliary line whitish; a line through eye olive-gray; under- 

 pays, shading on sides of head and neck, dull white, more or less tinged with yellowish; 

 flanks clearer yellow. Bill and feet horn-color. Adult male in fall and winter: Upper- 



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