GREEX, GREENISH GRAY, AND OLIVE 417 



small a shell. During the first week they double iu 

 weight every twenty-four hours, aud at the end of four 

 days, although still blind and naked, weigh as much as 

 a canary. Most of the food is given them by regurgita- 

 tion so long as they remain in the nest. They are 

 slow in developing, and do not fly until nearly four 

 weeks old. 



PLUMAGE GREEN, GREENISH GRAY, AND OLIVE 



429 BLACK-CHINNED HUMMINGBIRD. — ^rcMoc/«<^ 



alexandri. 



Family : The Hummingbirds. 



Length: xMale 3.30-3.75 ; female 3.90-4.10. 



Adult Male : Upper parts luetallic greenish ; under parts whitish, washed 

 witli green on the sides ; chin and tliroat velvety black, bordered be- 

 low by a broad band, metallic purple, green, and blue. 



Adult Female : Upper parts bronzy ; under parts light grayish ; tail 

 much rounded, with middle feathers green, next two tipped with 

 black, next three tipped with white. 



Young: Similar to adult female, but feathers of the upper parts mar- 

 gined with buffy. 



Geographical Distribution: Western United States, east to Rocky 

 Mountains, south over table-lands of Mexico. 



Breeding Range : From British Columbia south to Lower California, and 

 from the Pacific to the Rocky Mountains, chiefly in the upper Sonoran 

 zone. 



Breeding Season: May 1 to August 15. 



Nest : In trees or bushes, 4 to 7 feet from the ground ; of buffy plant 

 down covered with spider's web. 



Eggs: 2 or 3 ; white. Size 0.50 X 0.32. 



In some localities the Black-chinned Hummingbird is 

 known as the Purple-throated Iluinnier, and this seems 

 to describe him about as well as his more connnon name, 

 for just below tlie black chin is a band of iridescent 



27 



