462 BULLETIN 17 6, UNITED STATES NATIONAL MUSEUM 



to pester his mother with demands for food while she warmed her 

 eggs, but always waited patiently for her to come to him. As he 

 waited in his little thicket, he called slowly tink tink tink^ an utter- 

 ance that somewhat resembled the calls of the adult males on their 

 singing perches, but was much fainter and weaker. 



AVliile she incubated her first set of eggs, the mother found much 

 time for bringing additional cobweb and down to the nest, which 

 was so well finished that it did not appear to require further atten- 

 tion. The hastily built second nest was in far greater need of addi- 

 tional material; but now the hummingbird was too busy with other 

 things to give time to this and brought nothing to the nest during 

 the morning which I passed with her. She was now more atten- 

 tive to her duties and incubated more steadily; she camxC to and left 

 the nest only eight times in four hours, as compared with 23 times 

 during the same period of a morning while she incubated her first set 

 of eggs. Even during a seven minutes' recess from the nest, she 

 found time to satisfy her own himger and to gather food for her 

 fledgling. 



It seems to be the unhappy fate of hummingbirds that their nests 

 come to disaster even more frequently than those of other kinds of 

 birds, and the white-ears are no exception to this rule. The nine 

 completed nests I found in Guatemala in 1933 contained two eggs 

 each, making a total of 18. Three of these nests were destroyed in 

 some unknown manner while they still contained eggs, and one was 

 deserted. Only nine eggs hatched. Of the nine nestlings, one suc- 

 cumbed to the cold, two were probably taken by the Indians, and 

 three met unknown ends. Only three lived to leave the nest. 



Plumages. — Dr. Frank M. Chapman (1925) writes: "Young 

 females have the crown and upper parts more rusty than the adult, 

 the under-parts buffy white, the sides rusty rather than green. 

 Young males resemble the adult female, but usually have a few 

 metallic blue feathers on the throat or forehead." 



Dickey and van Rossem (1938) write of the closely allied race 

 pygmaea in El Salvador, where apparently the species breeds in No- 

 vember and December, just as in the neighboring Republic of 

 Guatemala: "A young male taken February 21 has nearly com- 

 pleted the post] u venal body molt, and the iridescent blue and green 

 feathers are rapidly filling in the chin and throat." 



Food. — ^Like other hummingbirds, the white-ears subsist largely 

 upon the nectar of flowers, which they supplement bj^ minute spiders 

 plucked from their webs and small volitant insects deftly snatched 

 from the air. They seem to have no particular preferences as to the 

 source of their nectar but visit indifferently a great variety of blos- 

 soms. At the beginninor of their nesting season in the Guatemalan 



