454 THE UNIVERSITY OF CALIFORNIA CHRONICLE 
variation also in the white and yellow markings on wings 
and tail. The yellow varies appreciably in depth of hue; 
on the wings it is sometimes replaced in part or entirely by 
white, and the size of the spots is then diminished. These 
various markings are not sexual and they are not seasonal. 
The sexes are alike, and every stage of variation may be 
found in a flock of winter birds, or in the summer. The 
inference has been made, and it is stated over and over again 
in the literature, that lack of red wing tips and the presence 
of paler yellow markings are indications of immaturity; 
that as the bird matures these features become richer and 
more elaborate, and that probably three or four years are 
required to attain the most perfect plumage. 
Yet, here, in a brood of five young birds (two of them 
figured herewith), we find that four of the five have as many 
red wing tips as are ever seen in older birds, and in all five 
the yellow markings are more vivid than in any adult 
examined, even than in molting birds with these feathers 
partly grown, hence absolutely fresh and unfaded. These 
were the first nestling Waxwings to be taken in America; 
previous conclusions as to the age at which the various 
characters became most perfect were all based upon the 
apparent probability that the most beautiful birds were 
the oldest. It 1s too bad that in demolishing such a theory 
one cannot offer as substitute another that will be as definite 
and as satisfying, but at present that does not seem possible. 
The facts may be summarized as follows: The Bohemian 
Waxwing is highly variable as regards certain ornamental 
features of plumage. The sexes are essentially alike and there 
is no seasonal change other than fading and wear produced 
upon the feathers. Breeding birds of either sex have been 
found with the ornamental markings highly elaborated; in 
other breeding birds such markings are almost totally absent. 
The same is true of specimens taken from winter flocks. The 
young bird has a distinct body plumage, differing somewhat 
from that of the adult, but the differences do not extend to 
the wing and tail feathers under discussion, and in this 
connection they may be disregarded. In the one brood of 
a 
