456 U.S. NATIONAL MUSEUM BULLETIN 23 7 part i 



her bill in his, and through my glasses I could glimpse the white, 

 viscid mass that he passed to her. Then he lifted his head slightly in 

 order to regurgitate a second portion. He passed her twenty-one 

 mouthfuls in this manner, then flew off for the night. 



"During my nine hom's of watching the male goldfinch gave his 

 mate seven substantial meals. She took only three brief recesses 

 from the task of incubation, totalling twenty-five minutes, and kept 

 her eggs covered 95.4 per cent of the time. Of ten other species of 

 finches that I have watched incubate, chiefly in Central America, 

 none has approached the goldfinch in constancy of sitting. The next 

 best, a Variable Seedeater (Sporophila aurita) covered her eggs only 

 81.2 per cent of nine hom*s, and she was by far the most faithful of 

 four of her kind whose nesting I studied. AU the other finches, big 

 and little, incubated between 60 and 75 per cent of the time, during 

 watches that lasted from 6 to 12 hours; a few received occasional 

 morsels from their mates, but none was substantially fed Hke the 

 goldfinch. Of all the passeriform birds whose mode of incubation I 

 have studied, of whatever family, the only one that matched the 

 goldfinch's record of constancy in sitting was the big White-tipped 

 Brown Jay (Psilorhinus mexicanus). Among these birds of the 

 tropical lowlands, the incubating female is fed by her mate and often 

 by one or more unmated helpers in addition." 



Eggs. — The goldfinch lays from four to six eggs with sets of five 

 being the most common. They are ovate with a tendency toward 

 rounded ovate, and have very little lustre; they are very pale bluish- 

 white and unspotted. Occasionally, an egg in a set will have a few 

 scattered spots of reddish brown, and rarely an egg will be found well 

 spotted with "vinaceous fawn." Harold M. Holland, of Galesburg, 

 111., writes that he has "a set of six eggs, taken locally August 7, 1946, 

 all of which are so thickly and distinctly spotted around their larger 

 ends as to be hardly recognizable, offhand, as goldfinch eggs." 



The measurements of 50 eggs average 16.2 by 12.2 millimeters; the 

 eggs showing the four extremes measure 20.0 by 11.5, 18.3 by 13.2, 

 14.2 by 11.7, and 15.2 hy 11. 4 millimeters. 



Young. — Henry Mousley (1930a) in a careful study of the nest 

 life of the goldfinch stresses the point that the young birds are fed at 

 long intervals, according to his experience much longer than is the 

 case in wood warblers. He remarks: "* * * during the twenty hours 

 I was at the nest, the young were fed on eighteen occasions, nine by 

 the male, and nine by the female, at intervals of about an hour, or to 

 be exact, once in every 53.3 minutes * * * ." Checking his obser- 

 vations the following year, he continues (1930b): "It was about 

 10:30 a.m. when I arrived at the site, and 3:30 p.m. when I left, and 

 during those five hours the young were fed eleven times, four by the 



