i6i


especially interesting for two reasons; (i) because of the assump¬

tion during the summer by the male bird of a plumage more or

less resembling that of the female; (2) because of the compara¬

tive ease with which hybrids may be bred from them ; most of

the hybrids being, I believe, fertile inter se. As showing the

interest attaching to judiciously bred hydrids, there was one

bred several years back at the Zoological Gardens between the

Ruddy Sheldrake, an Eastern bird, whose breeding range extends

from China to the Black Sea, and the Australian Sheld-duck.

The result of this cross was a bird very much resembling the

New Zealand Sheldrake, being evidently a throw back to a

primitive type. This is perhaps an extreme case, as many

hybrids have been bred, showing no special features of interest ;

nevertheless, for anyone with a convenient pond and a taste for

aviculture, a large field for the careful and judicial study of

hybridisation is open.


With regard to the first point, much remains to be studied.

The change of plumage may be best noticed in the common

Mallard. In this species, the male bird towards the end of May

begins to change into a brown plumage, similar, but not the same

as, that of the duck. This point, which was noticed by Mr.

Castellan in the Field , a few weeks back, appears to have been

curiously overlooked, and I can find no description of the bird

in this plumage; most of the books on the subject content

themselves with the remark, “During the summer the male

assumes female plumage,” without attempting to describe the

plumage. I may mention that the Mallard always retains a

yellow bill while the feathers on the rump are of a uniform dark

brown with no light edging. As soon as this change is nearly

complete, about the third week in June, it simultaneously loses

all its primaries and becomes temporarily unable to fly; by the

end of July, it has, however, regained its full powers of flight.


The first signs of the winter dress appear again about

the beginning of August, though it is not completed till the

middle of Odtober.


A change similar to this is undergone by the males of

all true British Surface-feeding Ducks, except the Sheldrake,

where the plumage of the sexes is practically identical; but

whether this species moults in summer as well as in autumn, or

becomes incapable of flight, I am unable to say.


With regard to the Diving Ducks, I have had no practical

experience, and am unable to find much in the literature on the

subject.



