INDIGO BIRD. 
101 
chiefly in the morning, being comparatively mute during the 
heat of noon ; but the Indigo Bird chants with as much anima- 
tion under the meridian sun, in the month of July, as in the 
month of May ; and continues his song, occasionally, to the 
middle or end of August. His usual note, when alarmed by 
an approach to his nest, is a sharp chip , like that of striking 
two hard pebbles smartly together. 
Notwithstanding the beauty of his plumage, the vivacity 
with which he sings, and the ease with which he can be reared 
and kept, the Indigo Bird is seldom seen domesticated. The 
few I have met with were taken in trap cages ; and such of 
any species rarely sing equal to those which have been reared 
by hand from the nest. There is one singularity which, as it 
cannot be well represented in the figure, may be mentioned 
here, viz. that, in some certain lights, his plumage appears of 
a rich sky blue, and in others of a vivid verdigris green ; so 
that the same bird, in passing from one place to another before 
your eyes, seems to undergo a total change of colour. When 
the angle of incidence of the rays of light, reflected from his 
plumage, is acute, the colour is green ; when obtuse, blue. 
Such, I think, I have observed to be uniformly the case, with- 
out being optician enough to explain why it is so. From this, 
however, must be excepted the colour of the head, which, being 
of a very deep blue, is not affected by a change of position. 
The nest of this bird is usually built in a low bush, among 
rank grass, grain, or clover, suspended by two twigs, one 
passing up each side ; and is composed outwardly of flax, and 
lined with fine dry grass. I have also known it to build in 
the hollow of an apple tree. The eggs, generally five, are 
blue, with a blotch of purple at the great end. 
The Indigo Bird is five inches long, and seven inches in 
extent ; the whole body is of a rich sky blue, deepening on 
the head to an ultramarine, with a tinge of purple ; the blue 
on the body, tail, and wings, varies in particular lights to a light 
green, or verdigris colour, similar to that on the breast of a 
peacock ; wings, black, edged with light blue, and becoming 
brownish towards the tips ; lesser coverts, light blue ; greater, 
