Adult. Upper surface continuously deep lateritious-rufous, all the lighter markings almost obliterated. Bars on the tail scarcely traceable. Black cervical transverse space conspicuous. Sides of the breast and stripes of the sides duller rufous than the tint above; white of ground-color with yellowish tinge; legs pale rufous, deepest on outer side, immaculate. Gular collar blackish.
♂ (43,055, La Palma, Costa Rica, January 27, 1866; José Zeledon). Wing-formula, 4=5, 3–6–2; first shortest. Wing, 3.80; tail, 2.40.
♀ (33,216, San José, Costa Rica; J. Carmiol). Wing-formula, 4, 3=5–6, 2; first shortest. Wing, 4.15; tail, 2.90; tarsus, .80; middle toe, .75.
The numerous specimens examined come from the Rio Grande of Texas (across the whole breadth of Middle America) to Paraguay, everywhere the same species, those from the extremes of its range showing scarcely any difference.
A specimen of the ferruginous plumage, in the collection of the Philadelphia Academy, is remarkable for the great intensity and uniformity of the rufous; the entire plumage, in fact, being of this color, a fine light tint of which replaces the white below. There is no trace of bars on either wings or tail.
In the very large series before me I find in individuals every possible shade between the two extremes described. Over fifty specimens have come under my notice.
Habits. This little Owl claims a place in our fauna on the strength of several specimens taken in Southern Arizona by Captain Bendire. It is a southern bird, found throughout the whole of Mexico, and ranges thence though the whole of South America, except the Pacific coast, as far south as Southern Brazil. In Mexico it is as abundant on the Pacific as on the eastern coast, and is by far the most common Owl of its genus found in that country.
Mr. E. C. Taylor states that he found this bird pretty common in Trinidad, where it is said to fly about in the daytime, apparently indifferent to the blazing tropical sun, and is much smaller than any other species of Owl he met with.