178 TlMEHRI. 
most typical examples of this met with in the colony are 
well-known, a reference to some of them might not be 
out of place, considering that at any rate they are not 
commonly known. Most residents are more or less 
familiar with such birds as the snowy bell-bird, the richly- 
coloured cock of the rock, and the equally striking 
cotingas, but these birds are known simply in their 
adult male plumage, the females and the young males 
being so differently coloured from their fully developed 
sire that, at first sight and merely from appearance, 
it would be concluded that no relationship existed 
between them. Recently the Museum collection has 
been enriched by the acquisition of series of specimens 
of several species which well illustrate these changes, 
and it is hoped that soon they will be available for 
inspection in the public exhibition cases. 
The campanero or snowy bell-bird presents one of 
the most marked examples. Here, as in the other birds 
generally, the colouring of the young males even when 
equal in size to the full grown bird, is so similar to 
that of the uniformly-coloured females, that it would be 
impossible to distinguish the one from the other, were 
it not that the young males possess the distensible ap- 
pendage by means of which the bell-note is rung — an 
appendage confined entirely to the male sex. In the 
females throughout life, and in the young males, the 
colour is a lively though pale green, touched with 
white, in powerful contrast with the pure milk-white 
of the adult males ; and every variety between the two 
extremes of male colouring is obtainable as the greenish 
tint gives place gradually to the eventual white. 
In other birds such as the cotingas, in which there are 
