The Lead-colored Bush-Tit 
Recognition Marks. —Pygmy size; nearly uniform gray coloration—crown 
not contrasting with back, as in P. minimus. 
Nesting. —Much as in preceding species, but nest a little shorter, 7 or 8 inches 
long, and more compactly built; sage leaves and dismembered hummingbirds’ nests 
are favorite materials, together with blossoms, catkins, cobwebs, etc. Eggs: av. 
13 x 10.2 (.51 x .40). 
General Range. — Resident in Upper Sonoran and Transition zones of the arid 
interior from eastern Oregon and western Wyoming south to Sonora and western 
Texas, and from southeastern California east to central Colorado. 
Distribution in California. —Resident in the Upper Sonoran zone in the east 
central desert ranges, and sparingly along the eastern slope of the Sierras from Carroll 
Creek north (at least) to Bridgeport (Aug. 2, 1918). 
Authorities.—Cooper ( Psaltriparus plumbeus ), Orn. Calif., 1870, p. 49 (“to 
Sierra Nevada, Cal. (?) Gruber"); Cones, Birds Col. Val., 1878, p. 125 (syn., desc., 
habits, etc.); Bendire, Proc. U. S. Nat. Mus., vol. x., 1888, p. 557 (habits; food; desc. 
nest and eggs; Ariz.); Swarth, Auk, vol. xxx., 1913, p. 399 (crit.; discussion of Psaltripa¬ 
rus plumbeus, P. m. lloydi, and P. santaritce) ; Auk, vol. xxxi., 1914, p. 520, map 
(crit.; distr., changes of plumage, etc.). 
While the Lead-colored Bush-Tit is lighter, grayer, and more uniform in color 
than examples of P. minimus, the degree of relationship existing between minimus 
and plumbeus is admittedly a closer one than can be accurately expressed in current 
nomenclature. 1 It is enough, perhaps, to understand this relationship on its own 
merits without forcing our knowledge into taxonomic moulds, whether new or old. 
Plumbeus is the bird of the central Southwest, and so of the central-southern, semi- 
arid ranges of eastern California. Along the eastern slopes of the Sierras, in Inyo 
and Mono counties, plumbeus overlaps the range of P. minimus californicus, and 
probably interbreeds with it. 2 We may conceive the two forms as having recently 
diverged (speaking phylogenetically—the process was really a very slow one, for 
Psaltriparus is a comparatively implastic type) from a common southern stock. From 
new differentiation centers, in Arizona and western California, respectively, and 
separated by a long interval, the two evolving forms have recently flowed toward each 
other (speaking distributively) until they now meet and hybridize along a narrow 
line, still undefined, in eastern California. 
ALTHOUGH undeniably different in color-tone from our more famil¬ 
iar California Bush-Tits, the lighter, grayer bird from the desert ranges 
does not appear to differ from its darker relative either in voice or action. 
Without pausing, then, to give it separate appreciation, 1 copy briefly 
some excellent notes furnished me by Mr. Frank C. Willard, lately of 
Tombstone, Arizona. In the Huachuca Mountains, near the recognized 
center of distribution for this species, Mr. Willard finds the Lead-colored 
Bush-Tits nesting chiefly in the oak trees, junipers, grape-vines, and 
firs, though occasionally in pine trees, and that up to a height of forty 
1 See Swarth in “The Auk,“ Vol. XXXI., Oct., 1914. pp. 522-524. 
2 lb., p. 221 and following. 
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