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Colour change without a moult.



The change of colour from young to aclult plumage in Paroaria

was, I believe, regarded as absurd by certain ornithologists ; but that

is certainly not the only group in which startling transformations

of juvenal into adult plumage are effected without a moult. Of

Agelasticus thilius, I purchased what purported to be a pair in 1894 ;

in the autumn the supposed hen died during its change from the

young to the adult male plumage (dissection proved it to be a cock

bird). In this specimen, which I have before me, the general tone

of the plumage is smoky rather than bluish-black as in the perfected

male feathering, a few feathers on the crown still retain partly brown

tips, as also most of those on the mantle ; the wing-coverts and

secondaries still retain their well-defined, red-brown borders ; the

throat feathers have their fringes partly white, but many of those on

the breast are in a transitional stage, some of the fringes being whity-

brown, whilst at the sides, on the lower abdomen, and vent this

colour is prevalent.


All bird-students agree that many birds gain their nuptial

plumage by shedding the tips or fringes of their feathers ; but we

have no right to assume that this is the case with all those which do

not pass through a regular spring moult. Our common Bedstart is

supposed to shed the tips of its feathers ; yet I have a male which

died during the change of plumage, and its colouring is intermediate

between that of winter and summer, but the fringes are not abraded.

Birds in a wild state are far more likely to get the edges of their

feathers rubbed off than those properly looked after in semi-captivity ;

so that if shot with partly abraded fringes to the feathers, they may

incline one to come to incorrect conclusions. In the case of my

Bedstart, two-thirds of most of the feathers of the hind-breast and

abdomen (and not the fringes alone) would have to be sacrificed in

order to acquire the summer colouring by abrasion.


I always like to give reasons for my views, but to those who

do not regard them as conclusive, I do not desire to be dogmatic ;

there is so much to learn and so little that we understand of the

workings of Nature that we can only conclude — “ Magna est veritas

et prevalebit.”



