ANNA'S HUMMINGBIRD 377 



crown and gorget changes to purple as a secondary color in some 

 instances, while in others gold and greenish lights are frequently 

 seen. Ridgway (1892) refers to this as "perhaps the most beautiful 

 of North American Humming Birds" and quotes Gould's Monograph 

 of the Trochilidae as follows: 



When studying the diversified forms and coloring of tlie Trochilidae, I have 

 frequently heen struck with the fact that those districts or countries having a 

 metalliferous character are tenanted by species of Humming Birds which are 

 more than ordinarily brilliant and glittering. This is especially the case with 

 the species inhabiting Mexico and California : in illustration of this assertion, 

 I may cite the three California species, Selasphorus rufus, Calypte costae, and 

 the present bii-d, C. annae, all of which are unequaled for the rich metallic 

 brilliancy of certain parts of their plumage, by any other members of the 

 family. The two latter, C. costae and C. annae, have not only the throat, but the 

 entire head as glitteringly resplendent as if they had been dipped in molten 

 metal. 



Food. — The food of the hummingbird is divided quite definitely 

 into two classes: Carbohydrates, consisting of the nectar of flowers 

 and more rarely of fruit juices and the sap of trees; and proteins, as 

 furnished by the minute insects and spiders obtained either in con- 

 junction with the other food or as the product of separate hunting 

 activities. In late afternoon or on a cloudy day a hummingbird may 

 frequently be seen perched upon some exposed twig or wire, from 

 which it sallies forth at intervals to engage in strange aerial evolu- 

 tions that might well mystify a stranger, since the flying insects it 

 pursues are too small to be discerned at any distance. A specific 

 instance of this sort is thus described by Frank F. Gander (1927) : 

 "On the morning of Thanksgiving Day, November 25, 1926, in Balboa 

 Park, San Diego, California, I watched three male Anna Humming- 

 birds {Calypte a7ina) catching insects on the wing. A rain the night 

 before had cleared the air and I could easily see the sun glistening on 

 the gossamer wings of a host of tiny midges flying all about me in 

 the air. The male hummers would hang on rapidly vibrating wings 

 for a second and then dart suddenly a short distance and one of the 

 glistening insects would disappear. This was repeated time and time 

 again, and the birds seldom missed ; on the rare occasions when they 

 did miss they relentlessly pursued their chosen prey until it was 

 captured." 



Many observers have mentioned the hummingbirds' habit of search- 

 ing the trunks and branches of trees for animal food and of extracting 

 from spiders' webs small entangled insects or even the proprietors 

 themselves. In their account of Anna's hummingbird in the Yosemite 

 Valley, Grinnell and Storer (1924) have described some of its lesser- 

 known feeding habits : 



During November and December of 1914 we saw individuals almost daily at 

 El Portal. At this time of the year there were no flowers of any sort to be 



