The Costa Hummer 
though they are not. known to breed within hundred miles. Northern 
"winter" records (really late fall) also exceed the breeding records by a 
degree or so. There is evidently some uncertainty attendant upon the 
autumnal retreat and there are a number of desert or Lower Sonoran 
records for winter, but none for the breeding season. 
No. 185 
Costa's Hummer 
A. O. U. No. 430. Calypte costae (Bourcicr). 
Description. — Adir.’ niuk: Head around, with Jatero-posterior extension of 
throat feather.- metailie violet -purple, changing to velvety black or with light blue 
reflect;-ms; flight-feathers and later::! re d- . purplish dusky: remaining upperparts 
shining bronzy green (golden green or peacock-blue with changing angle of vision): 
dusky shading of underparts nearly confined to wing-linings; sides of breast and centers 
of lower • ail-coverts (u here overlaid v. ii h hron/y green) shading through buffy of chest 
to clear white in definition of gorget: h : wral i efts and edges of lower tail-coverts white; 
tail double-routided, the uttermost!- uher cry narrow. Biil straight, black;feet black. 
Adult female: Without metallic feathers on head, save for flecking very variable in 
_ , ead and 
Losta s Hummer 
Male and female, about life size 
From a uater-color fainting by Allan Brooks 
nargined with bufty; throat 
more heavih shaded and gorget of adult outlined, (he metallic feathers first appearing 
or, the lower portion of the throat. Young female; Like adult female, but drab of 
head more exo-nsi mi. a ! ihroat unflecked. Length >c-ves about equal): 85.1 (3.35); 
wing 44.4 (1.73); tail 22.fi (..Ho); bill 17.2 (.68). 
Recognition Marks, y >, .• size; viola-purple gorget and crown of male 
distinctive; tiu- female. ..ithougi; a b ,it- -m.d v distinguishable in the field 
from that of A. nkmndri. Indeed, the 01 i; certain distinction in hand is generic — 
C. costa lacks the curious tooth at the sub) ri final angle of the inner web of the inner 
primaries, which i- he subtle birthmark of the genu? Archilochus. A ready but by 
no means infallible held dis I ;ion is, however afforded by the difference in nest 
structure (q. v.). 
Remark.—The nearly distinction-defying similitude of the females of Calypte 
costa and A rchiloch;. cl- 'are:: ought to guard K.xonomers against the folly of generic 
separation of these tv.o croup.-.. The males. Ire sure, are strikingly, though quite 
superficially, divergent in two respects; viz., the invasion of the crown by metallic 
feathers (in the Otiybte group) and the reduced inner primaries of the Archilochus 
group. But ail distinction? in the case of the females reduce to a pitiful atom of a 
projection or the web hi re . •, tain primaries tin Archilochus ),—a fairy wisp of evi¬ 
dence v rich would scarcely scr\ - t-.v distinguish twins to their own mother. 
Nesting.— Acs/: Of Id. variable construction; typically a dainty cup of 
vegetable downs, decorated externally with yellow-sered or gray leaves and plant- 
946 
