124 ^ 
BEAUTIFUL BIRDS. 
colours are subject to considerable variatiou in different 
specimens ; as, for instance, the throat is every shade 
from golden green to a rich golden yellow, and when 
this part is more inclined to yellow, all the rest of the 
bird is of a paler tint ; hut whether these variations 
are the result of difference of age or season, or whether 
they are permanent for the life of the birds, has not 
been ascertained. 
The produced feathers on the flanks and in the tails 
of these birds are among the most remarkable of 
their external characters. Those which originate in 
the flanks are of a pale yellow or straw colour for the 
greater part of their lengths, but they are marked 
with purplish-red towards their origin. It is dif- 
ficult to imagine any structure more beautiful. 
The shafts are finely tapering, and the fibres of the 
webs, which are quite detached from each other, have 
secondary ramifications ; and the whole are fined off 
towards the extremities, so that they really more re- 
semble the tail of a comet tlian they do any more solid 
matter ; but unsubstantial as they seem toward their 
extremities, the shaft and web are so well proportioned 
to each other that the whole feather floats far and 
gracefully, and with the very maximum of tenuity it 
has no appearance of weakness. Besides those, there 
are two very peculiar filaments of feather, covered 
with velvety down, interspersed with short stiff hairs, 
which have, however, nearly the same lustre as the 
down, which originate one on each side of the rump, 
and both extend to nearly the length of two feet. 
These are yellowish at their bases ; but for the greater 
part of their length they are nearly black, and show a 
