It is both diurnal and nocturnal, and feeds at all hours. Outside the town of San Juan, which lies upon the eastern base of the Andes, Mr. Bishop had a fine opportunity to watch their habits in a locality differing entirely from the pampas. The country around San Juan is a dreary desert, covered with low thorn-trees, and over this waste a few Owls are found, principally near the town itself, in the vicinity of the pastures that are cultivated by irrigation. They mate in September and October. “One evening,” Mr. Bishop writes, “I was attracted by a strange sound that I supposed proceeded from a frog, but it proved to be the love-note of a little _Athene cunicularia_, and which was answered by its mate. It alighted upon a post, and commenced turning around upon it, with throat dilated, and emitting a guttural sound. These antics were continued for more than a minute, it occasionally bowing its head in a mysterious manner. The female soon after joined it, and they flew away. Each night it perched upon a tall flagstaff and uttered its love-note. Close by the house was a lagoon, the borders of which were swampy, and over this a pair often hovered in search of food. I watched one that kept on the wing for nearly two hours, some fifty feet from the ground, and during that time did not change its position in any other way than by rising or falling a few feet. A boy brought me a female with five eggs, that had been taken from a burrow five feet from the mouth. The bird was very fierce, and fought me with her wings and beak, uttering all the while a long shrill note, resembling a file drawn across the teeth of a saw. I supplied her with eleven full-grown mice, which she devoured during the first thirty-six hours of her confinement. It is said to place a small nest of feathers at the end of the hole, in which are deposited five white eggs.” The eggs of the var. _cunicularia_ are of a rounded-oval shape, more obtuse at one end than at the other, measure 1.30 inches in length by 1.05 in breadth, and are of a uniform white color, with a slightly bluish tinge. [Illustration: =6885= ½ NAT. SIZE. _Strix pratincola._ (See page 10.)] The egg of the _A. hypogæa_ is of a rounded-oval shape, equally obtuse at either end, and averages 1.35 inches in length by 1.13 in breadth, and is of a uniform clear white color. This description is taken from an egg obtained by Mr. E. S. Holden near Stockton in California. Captain Bendire writes that he has found as many as nine, and once even ten, eggs in the nest of the North American species. NOTE.