J74 'HE CHICKADEE. ' 



(icucral RaiiKC — Eastern NOrtli Aimrica nortli of the l'i>t<>mac ami ( )liio 

 \'allcy!>. "A Mparalc 'ciilnny' inlialiil- llic ana IkIwci-ii tlic KiK-ky Mountains 

 and the Cascade Range, in eastern Wasliington (Walla Walla. I%llen>biirg, etc.), 

 western Idaho I I.eini. I'ort Sherman, etc.), and central I'lritish Columbia ( Sica- 

 ninres |Sicamoos|, L'linton, Ashcroft, etc.).*" — Rijlgway. 



RanKc in Washington. — .\s above. 



Authorities. — /'. a. occuh-iitnlis Brevster, I!. \. O. C. \II. 1882, 228 

 I Walla Walla). J. If this colony i>roves to be completely isolated, as claimed, 

 the bird should. i>erha|>s, be se))aralely named, and I would siifjjjcst I'cittliiSlfS 

 atricafiilliis fortuitus. 



Specimens. — I!. 1''. 



Till'". Chickadees of eastern W'ashin^'toii, cast of the Cascade foothills, 

 alonj,' with tliuse of northeastern OrejjiMi. western Idaho, and southwestern 

 Ijritish Columbia, are notably larger and brighter than P. o. otciiiriilalis. 

 In these and other regards they exactly reproduce the characters of P. 

 iiiricapUhis. which is a bird of the eastern L'niled States, and fioni whidi 

 tliey are widely separated by P. a. scptculriomilis. N'ow Chicka<lees are 

 resident wherever found. The most severe winters do not sutVice ti> drive 

 tbein south, anil they are subjected to such uniform conditions as tend to 

 insure stability of ty|)e. once adjustment to local environment is accomplished. 

 W'c have here, therefore, either an exami)le of a colony widely separated 

 from the |)arent stock, ami remainiii}:; inflexible imder alien conditions, or 

 else an indistinguishable reduplication of another form not closely related in 

 time thru the interaction of similar conditions. If the latter sujiposition be 

 the true one, and it probably is. we h.ive in this bird a theoretical sub- 

 species, but one which we cannot describe or <listinj;uisli in other than geo- 

 graphical terms. 



The case is somewhat similar with our Xighthawks iC. 7ir<ii)iiiiiiiis 

 siihsf>.) and Sparrow Hawks I Palco spancriiis snhsp.). but the problem in 

 these instances is further comi)licaled by the op])nrtunities of migration. 



