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



and unspotted. Dawson (1923) gives the average measurements of 

 10 eggs as 22.5 by 15.6 millimeters. 



The measurements of 40 eggs average 21.6 by 15.7 millimeters; the 

 eggs showing the four extremes measure 24-1 by 17.0, 23.1 by 17.5, 

 19.7 by 15.6, and 21.6 by 1^.8 millimeters. 



Young. — Dawson (1923) writes: 



The pace of the Leuco day quickens when these white ovals part and naked 

 babies, to the number of four or five, are born into this world of snow-glare and 

 hunger. The parents, however, have capacious throats, or crops, and to obviate 

 the handicap of a long haul, comparatively infrequent visits are made to the 

 nest. I have seen parents making trips every five minutes, but ten- or fifteen- 

 minutes are more usual, with half an hour, or such a matter, for older birds. Food 

 material rarely protrudes from the parental beak, but the nature of the visit, 

 whether parental or conjugal, may be surely determined by the presence or absence 

 of the foecal sac, the laden diaper, without which no self-respecting parent will 

 quit the presence of his (or her) offspring. * * * 



Alden H. Miller (1941) has made the interesting discovery that 

 rosy finches are provided with "buccal food-carrjdng pouches," 

 which facilitate carrying considerable quantities of food from distant 

 feeding grounds to nests. These are fully described and illustrated 

 in his article, to which the reader is referred. 



Dixon's (1936) observations indicate that the female does all the 

 incubating and will not tolerate the male near the nest until after the 

 young have hatched; from then on the male seemed to do more than 

 half the feeding; the young remained in the nest about 14 days and 

 were fed after leaving it. 



Food. — Grinnell and Storer (1924) write: 



Our findings in the Yosemite Park and elsewhere along the Sierras tend to show 

 that the food of the Leucosticte even in summer consists predominantly of seeds, 

 with possibly buds, of the dwarfed plants wliich grow at and above timber line. 

 Tliis is contrary to the testimony of several observers, who, upon seeing the birds 

 hopping about the edges of snow banks where numbers of benumbed insects are 

 often seen stranded on the snow, conclude that the birds are engaged solely in 

 gathering these "cold-storage bugs." * * * 



The present contention as to the prevalently vegetable character of the food of 

 the Sierra Nevada Rosy Finch is upheld by the contents of the crops of several of 

 the birds taken for specimens in August, 1911, in the Mount Whitney region. 

 These crops, ten in number, were subjected to careful examination and their con- 

 tents found to consist 91 per cent of small seeds, and 9 percent only of insects. 



Dawson (1923) writes: 



As the season advances and the area of the snowfields is reduced, the Leucos re- 

 sort to the south slopes of the peaks, where yellow-winged locusts and deer-flies 

 and the hardy butterflies, notably Vanessa californica, hold forth. These they 

 pursue on the ground, or else seize in midair by dextrous leaps from below. They 

 feed also at the lower levels over the heather beds and in the vicinity of the cirque 

 lakes. Once I saw a company of these Leucos feasting on caddis-flies. So eager 

 had they become that they alighted upon the stones wliich protruded above the 



