397 
THE GOLIATH A RATO 0. 
large, sharply curved, and having its cutting edges two-toothed, while the lower mandible is 
comparatively small, and only furnished with a single tooth. 
It is a native of New Guinea and the neighboring islands, and is not a very common bird, 
although specimens may be found in several museums. The peculiar formation of the tongue 
and beak would lead the ob- 
server to suppose that its habits 
must be different from those of 
ordinary Cockatoos ; but as lit- 
tle or nothing is known of its 
mode of life in a wild state, 
the precise use of these organs 
is rather problematical. 
In size, this bird is one of 
the largest of the Parrot tribe, 
being equal to and in some 
cases exceeding that of the 
great macaws, although the 
absence of the long tail renders 
it a less conspicuous bird. The 
general color of this species is 
deep black, with a greenish 
gloss, caused chiefly by the 
large amount of whitish powder 
which is secreted in certain 
imperfect quills, and thence 
scattered among the feathers, 
gi ving them a kind of ‘ ‘ bloom,’ ’ 
like that of the plum or grape. 
This substance is found 
very largely in most of the Par- 
rot tribe, and I well remember 
getting my coat powdered like 
that of a miller from playing 
with a great white Cockatoo. 
Many other birds, such as the 
vultures, possess this curious 
powdery substance, whose office is rather doubtful. The powder is produced from the forma- 
tive substance of the quill, which, instead of being developed into shaft and web, as in the 
case of the perfect quills, dries up and is then thrown off in a dusty form. The imperfect 
quill-feathers can generally be seen intermixed with the rest of the plumage wh 
bends down its head or plumes itself, and the white substance may 1 lu eke open ends 
of the imperfect quills, or lying thickly about them. In the case of vultures it is thought 
to be given for the purpose of keeping their skin and plumage ur jiiied by the putrid animal 
substances on which those unclean and useful birds feed, but is it is found in equal plenty on 
the Cockatoos, than whom no cleaner feeding or more fast' us birds exist, it is evident that 
it must serve some purpose that is common to thes wo dissimilar species. Very little 
structure is found in this dust when placed under j microscope, but with the aid of the 
polarizer I have made out several well-marked he ;onal cells. 
The green-black hue extends over the whole the plumage, but around the eye is a large 
naked space of skin, red in color, and covered oh wrinkles. The head is ornamented with a 
large and curiously formed crest, which is c posed of a number of single feathers, each being- 
long, narrow, and the web rather scanty. The color of the crest is rather grayer than the 
remainder of the plumage, probably on account of its less massive construction, and its free- 
dom from the white powdery dust which as just been described. In general the crest lies 
GOLIATH ARATOO .— Microglossus aterrimus. 
