74 Reviews, Notices, Etc.


history," the author proceeds to discuss the development of

chequers and bars on the plumage of various Columbtz, his

studies leading him to the conclusion that the chequers are of

very ancient origin, and (as I understand him) that the bars have

been evolved from them : this is certainly not the conclusion to

which a study of the nestling plumage of some at least of the

African doves leads me, inasmuch as the conspicuous spots on

the scapulars and inner secondaries appear in the adults with the

disappearance of the juvenile bars. But the paper requires far

more careful thought and consideration than can be given to it

in a brief review. A. G. B.



THE SPRING MOULT OF THE AMERICAN

LAUGHING GULL*


Some important observations, throwing much light on the

question as to whether the summer plumage of those birds in

which seasonal changes take place, is effected by a direct moult

or by colour change in the feathers themselves, have been carried

out by Mr. C. W. Beebe.


The subject of his observations was a Laughing Gull,

Lartis atricilla, the American representative of our common

Black-headed Gull. This bird was reared from the egg in the

New York Zoological Park, and the change of plumage from the

white-headed winter dress to the summer dress in which the

entire head is a dark slate colour was very carefully observed,

with the result that overwhelming proof was obtained that the

change is effected by a complete moult, and not by any colour

change in the feathers themselves whatever.


The new feathers, which are a dark slate-colour tipped

with white, grow up between the old white feathers of winter

which are gradually shed. As soon as the new feathers attain

their full size the white tips break off, leaving the uniform dark

hood.


THE SWANS.


Mr. C. W. Beebe, the Curator of Birds at the New York

Zoological Park, sends us a copy of a paper from his pen, re-


* The Spring Moult of Larus atricilla, Linn. By C. William Beebe.

From 'The Auk.' Vol. XXII., No. 4. October 1906.



