THE CHESTNUT-BACKED CHICKADEE. 281 



ft'alurc of llif interior conslruclion was a knot, which had persisted as a liard 

 core when tlie surrounchng i)uni< liad l)een removed. This had evidently been 

 no end of aniusenient to the yonng I)ird.s and of service to the ])arents as well, 

 for its sm'face was polished l\v the friction of many Peniliestine toes. 



No. 109. 



CHESTNUT-BACKED CHICKADEE. 



.-\. O. L'. Xo. 741. Penthestes rufescens Towns. 



Description. — .Idiilts: Cmwn and nape dull sepia brown beconiing sooty 

 toward lateral border — black before and behind c}e. separated from sooty black 

 throat patch by large white area broadening jjosteriorly on sides of neck ; back, 

 sca])ulars, rnnip, and sides of body rich chestnut ; lesser wing-coverts grayish 

 brown: npper tail-coverts hair-brown or more or less tinged with chestnut; wmgs 

 and tail deeper grayish brown edged with jjaler gray ; remaining under])arts 

 (centrally) white; under tail-coverts washed with brownish; bill black; feet 

 brownish dusky; iris brown. The brown of crown and hmd-neck deepens in 

 winter. Young birds are duller in coloration, especially as to the chestnut of back 

 and sides. Length about 4.75 ( i20.(!) ; wing 2.35 {60) ; tail i.(;o (4S.3) ; biil .37 

 (9.5) ; tarsus .65 (16.5). 



Recognition Marks. — Pygmy size ; chestnut of back and sides distinctive — 

 otherwise not easily distinguished in the tree-tops from P. a. occidcntalis. Fre- 

 c|uents thicker timber and, usually, drier situations. 



Nesting. — Nest: in hole of dead stub, usually some natural cavity enlarged 

 and customarily at moderate heights, 10-20 feet, a couch of hue bark-shreds, green 

 moss, etc., heavily felted with sfjuirrel-, rabbit-, or cow-hair, and other soft 

 substances. Ec/gs: y-cj, pure white as to ground and sparingly s])rinkled with 

 reddish brown dots, chiefly about larger end. Av. size, .61 x .47 (i5.5.\' 11.9). 

 Season: April 25-June 15 (according to altitude) ; one brood. 



General Range. — Pacific Coast district, from northern California to Alaska 

 ( Prince William Sound and head of Lynn Canal), east to Montana. 



Range in Washington. — Resident ; abundant and thoroly distributed thru 

 forests of Olympic Peninsula and Puget Sound region, decreasing in numl)ers 

 from Cascade divide eastward (in heavier coniferous timber only). (We have 

 no records of its occurrence east of Stehekin.) 



Authorities.. — Pants rufescens Townsend, Journ. Ac. Nat. Sci. Phila. XII. 

 1837, 190. T. C&S. L'. Rh. Kb. Ra. P.. E. 



Specimens. — U. of W. P. Prov. I'. E. 



W'lLVT busy little nn'dgets these are as they go trooping thru the tree- 

 tops intent on jjlunder! .And what a merry war they wage on beetle and nit 

 as thev scrutinize everv cre\ice of bark and bract! The bird cats insects at 



