Birds of America 
(State Bird of Colorado)
By John James Audubon, F. R. SS. L. & E.
VOLUME III.
PRAIRIE LARK-FINCH.
[Lark Bunting.]
CORYDALINA BICOLOR, Towns.
[Calamospiza melanocorys.]
PLATE CCII.--MALE AND FEMALE.
This species, of which there are in my possession several specimens, presented to me by my friend Mr. NUTTALL, was discovered by that zealous naturalist and his companion Mr. TOWNSEND on the plains of the Platte, and briefly characterized in the Journal of the Academy of Natural Sciences of Philadelphia. From its general appearance, and especially from what is known of its habits, I consider it closely allied to the Rice Bunting, Dolichonyx oryzivora; I have adopted the appellation given by its discoverers, the latter of whom has favoured me with the following notice respecting it.
"The Prairie Finch inhabits a portion of the Platte country, in large flocks. It is strictly gregarious, and feeds upon the ground, along which it runs like the Grass Finch, Fringilla graminea, to which it is somewhat allied. As the large flocks, consisting of from sixty to a hundred individuals, were started from the ground by our caravan in passing, the piebald appearance of the males and females promiscuously intermingled, presented a curious, but by no means unpleasing, effect. While the flock is engaged in feeding, the males are frequently observed to rise suddenly to a considerable height in the air, and poising themselves over their companions, with their wings in constant and rapid motion, they become nearly stationary. In this situation they pour forth a number of very lively and sweetly modulated notes, and at the expiration of about a minute descend to the ground, and course about as before. I never observed this bird to the west of the Black Hills."
Mr. NUTTALL'S notice respecting it is as follows:--"On the 24th of May, soon after crossing the north branch of the Platte, we met with this very interesting species of Fringilla. The males associated in flocks with the Cow-birds, uttering a most delightful song. Towards evening in particular, we sometimes saw them in all directions around us on the hilly grounds, rising to a little height, hovering and flapping their wings, at the same time singing something like weet, weet, wt, wt, wt, notes betwixt the hurried warble of the Bob-o-link, and the melody of the Sky Lark. It is in short one of the sweetest songsters of the prairie, is tame and unsuspicious, the whole employment of the little band being an ardent emulation of song."
FRINGILLA BICOLOR, Prairie Finch, Towns., Jour. Acad. Nat. Sc. Phil.,vol. vii. p. 189
PRAIRIE FINCH, Fringilla bicolor, Aud. Orn. Biog., vol. v. p. 19.
Adult Male.
Bill short, robust, conical, compressed; upper mandible a little narrower, with the dorsal line very slightly convex, the ridge slightly prolonged on the forehead, the sides convex and bulging, the edges direct, the gap-line nearly straight, deflected at the base, the tip sharp and a little exceeding that of the lower mandible; the angle of the latter short and very broad, the dorsal line ascending and slightly convex, the back broad, the sides rounded, the edges inflected, the tip pointed. Nostrils basal, oval, in a very short deep depression, nearly concealed by the feather's.
Head rather large; neck short; body full. Feet of ordinary length, rather strong; tarsus of moderate length, compressed, anteriorly covered with seven scutella, behind with two plates meeting so as to form a very thin edge; toes of moderate size, the hind toe stouter, the lateral equal. Claws rather long, arched, much compressed, laterally grooved, tapering to a very acute point.
Plumage soft and blended, the feathers ovate and rounded. There are distinct but small bristles at the base of the upper mandible. Wings of moderate length; the outer three quills nearly equal, the second being longest, the fourth slightly shorter than the third; outer secondaries broadly rounded and emarginate; inner tapering to a rounded point, one of them, when the wing is closed, little shorter than the outer primaries. Tail of moderate length, a little rounded, the lateral feathers shorter than the longest by two and a half twelfths.
The bill is light blue, the upper mandible somewhat dusky along the ridge; the feet and claws reddish-brown. The general colour of the plumage is greyish-black, the rump blackish-grey. The quills are blackish-brown, the inner secondaries black. There is a large patch of white on the wing including some of the smaller coverts, the tips of the first row, and the secondary coverts; the primaries and outer secondaries are narrowly, the inner secondaries broadly margined with white, with which most of them are also tipped. The middle tail-feathers are black, the rest brownish-black, all narrowly edged with white, and having a narrow speck of the same at the end of the inner web. Some of the feathers on the abdomen and the lower tail-coverts are also tipped with white.
Length to end of tail 7 inches; bill along the ridge (7 1/4)/12, along the edge of lower mandible 7/12; wing from flexure 3 5/12; tail 2 8/12; tarsus (11 1/4)/12, hind toe (4 1/4)/12, its claw (4 1/2)/12 middle toe 8/12, its claw 3/12.
Adult Female.
The female, which is smaller than the male, differs greatly in colour. The bill is dusky above, pale beneath; the feet as in the male. The upper parts are greyish-brown, streaked with dusky brown, the lower white, with oblong spots of brownish-black, the abdomen nearly pure, the sides tinged with reddish-brown. The quills are dark brown, edged and tipped with reddish-white, and the patch on the wing is of the same tint. The tail feathers are also dark brown, the outer externally edged, and all tipped with white on the inner web.
Length to end of tail 6 1/2 inches; bill along the ridge (5 1/4)/12; wing from flexure 3 1/2; tail 2 5/12; tarsus 11/12; hind toe 4/12, its claw 4/12; middle toe (7 1/2)/12, its claw (3 1/4)/12.