BICKNELL'S THRUSH. 



f oundland* ; it winters in northern South America. It was 

 named for Miss Alice Kennicott of Illinois. 



Bicknell's Bicknell's Thrushf is very similar to the 



Thrush preceding of which it is a subspecies, the 



Hylocichlaaliciatj.^ f . 



bicknelii difference is rather one of size more than 



L. 7.00 inches anything else. It is a mountain species with 

 May asth a SO ng remarkably like that of the Veery 

 especially in its tonal quality. The colors are practically 

 the same as those of the Gray-cheeked Thrush, but the 

 upper parts, especially the tail, are a trifle darker and 

 browner; indeed it may be called the darkest of all the 

 Thrushes, although I should call that difference very tri- 

 fling. But the differences between the Thrushes when 

 we compare their songs are absolute and invariable. The 

 nest of Bicknell's Thrush is built in a stunted tree or low 

 bush, generally in the recesses of the tangled growth of 

 dwarf spruces or firs on the shoulder or crest of some 

 mountain of the northeastern States, at an altitude of not 

 less than 2500 feet. Its structure is similar to that of the 

 Gray-cheeked Thrush, the egg, perhaps, is a greener blue 

 more finely speckled than that of the Olive-backed Thrush. 



The song of this Thrush is interesting, but is not com- 

 parable with that of the Hermit or the Olive-back. Its 

 close resemblance to the song of the Veery inclines one to 

 question whether the two species may not be more nearly 

 related than the ornithologist has determined; but that the 

 music of a given species should be accounted a diagnostic 

 point in matters of relationship with other species probably 

 would draw only a smile from the skeptical ornithologist who 

 prefers scientifically to depend upon bones and feathers.J 



But compare the records of the songs of the Veery on 



*Vide Report on Natural History Collections made in Alaska. 

 Edw. W. Nelson. 



f Named for Eugene P. Bicknell, its discoverer. 



t That, however, leaves two unaccountably similar birdsongs in 

 the lurch the origin of which the scientist has been at no pains to 

 discover. Now, it seems to me a perfectly logical conclusion that 

 strikingly similar effects are deducible from a common cause, and 

 one is justified in concluding that the common ancestry of Bick- 

 nell's Thrush and the Veery are identical on the basic idea that 

 differences in dimensions and color are due more to environment 

 than to inheritance. 



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