BIRDS OP NORTH AND MIDDLE AMERICA. 463 



Range.- — More northern portions of northern hemisphere; south in 

 the Nearctic region to high mountains of Nicaragua. (Two or three 

 species, one of them circumpolar.) 



KEY TO THE AMEKICAN SUBSPECIES OF CBETHIA PAMILIAEIS. 



a. Paler; under parts decidedly white (the flanks and under tail-ooverts more or less 

 tinged with buff) ; rump tawny. 

 h. Upper parts paler, with darker ground color decidedly brown, and color of 

 rump more ochraceous. (Northern Europe.) 



Certhia familiaris familiaris (extralimital).« 



hh. Upper parts darker, with darker ground color more sooty, and color of rump 



more tawny. 



c. Larger (wing averaging more than 65 mm. in male, more than 62 in female). 



d. Browner above, with streaks more buffy, and less purely white beneath; 



smaller, especially the bill; adult male averaging wing 65.5, tail 63.7, 



exposed culmen 13.9; adult female, wing 62.9, tail 61.2, exposed culmen 



12.9. (Eastern North America. ) Certhia familiaris americana (p. 464) 



dd. l^ess brownish above, with streaks purer or more grayish white, and more 

 purely white beneath ; larger, especially the bill; adult male averaging 

 wing 66, tail 65.1, exposed culmen 16.4; adult female, Aving 64.1, tail 

 63.6, exposed culmen 15.2. (Rocky Mountain district, from New Mexico 



to Cook Inlet, Alaska.) Certhia familiaris montana (p. 467) 



cc. Smaller (wing averaging less than 64 in male, less than 61 in female) . 

 d. Less tawny above, purer white beneath; larger (adult male averaging wing 

 63.5, tail 60.8, exposed culmen 16.2; adult female, wing 60.4, tail 57.2, 

 exposed culmen 14.7). (Mountainsof California to eastern British Colum- 

 bia. ) Certhia familiaris zelotes (p. 468) 



dd. More tawny above, more huffy white below; smaller (adult male averag- 

 ing wing 61.9, tail 61.2, exposed culmen 15.2; adult female, wing 60, 

 tail 55.6, exposed culmen 12.9). (Pacific coast district, from northern 

 California to southern Alaska.)... Certhia familiaris occidentalis (p. 470) 

 aa. Darker; under parts pale brownish gray (white only on chin and throat); rump 

 chestnut. 

 6. Browner, the streaks of upper parts narrower and more brownish or huffy, 

 on a more sooty ground color. (Mountainsof southern Mexico to Guatemala). 



Certhia familiaris alticola (p. 471) 



66. Less brownish, the streaks of upper parts more purely white, broader, on a 



clearer blackislj ground color. (Mountains of northwestern Mexico and 



southern Arizona.) Certhia familiaris albescens (p. 472) 



« [ Ceri/iia] /ami'Karis Linnieus, Syst. Nat., ed. 10, i, 1758,118 (based on Fauna 

 Suecica, 213, etc. ) ; ed. 12, i, 1766, 184. 



The discrimination of the several European forms of this species has been only 

 imperfectly done, and their synonymy is therefore involved in much uncertainty. 

 Consequently, I shall not attempt to cite references which may or may not belong 

 here. (See Hartert, Novit. Zool., iv, 1897, 136-139; Helhnayr, Tierreich, 18 Lief., 

 1903, 205-210.) 



