139 
BLUE-GREEN HUMMING-BIRD. 
Trochilus cyaneus. — Vi rillot. 
Plate VII. 
Oiseau-mouclie verazur, Omismya cyanca, Lesson , Ilistoirs 
Nalurelle des Oiseaux-mouches , pi. lxxi. p. 199. 
This species was discovered in Brasil, by MM. 
Langsdorfl' and Delalande, and, according to Lesson, 
was first described by Vieillot, in 1818. It is of 
small size, being scarcely three inches in length, in- 
cluding the bill and tail. The bill is of a clear yellow, 
brownish at the tip, slightly dilated at the base ; the 
crown is of a dull green, changing with the light to 
a pure and brilliant blue ; the throat is a mixture of 
grayish and rich ultramarine blue, according to the 
position, and in the centre has the plumes of a scaly 
form and of a brighter hue ; the neck, back, and lesser 
wing-coverts, are of a golden green ; the rump and 
tail-coverts green, with reddish or bronze reflections ; 
the wings, equal in length to the tail, are narrow, 
and of a purplish black ; the tail is slightly forked, 
and of a uniform steel blue ; the breast green, or clear 
blue, according to the position, changing to brownish 
