Dr. Cooper, on the other hand, relates an instance where one of these Owls resided as an inmate in a dove-cot, where it was not known to do any injury to its inmates. The Screech-Owl can hardly be said to construct any nest, but lines the hollow in which it rears its young with a few loose leaves, dry grasses, and feathers. The eggs are usually five or six in number; they are pure white, and nearly round. Their average measurement is 1.38 inches in length by 1.19 in breadth. In regard to the distinctive peculiarities of var. _maccalli_, we are in possession of but little information. Its habits probably do not essentially vary from those of the common _Scops asio_, which it so closely resembles in other respects, and of which it is to be regarded as a geographical race. It was first taken by Mr. E. S. Holden, near Sacramento, and described by Mr. Lawrence as the _Ephialtes choliba_ of Vieillot. It has since been found in other parts of California, in Northern Mexico, Arizona, and on the Rio Grande. It was obtained in Tamaulipas—where it is evidently rather common—by the late Dr. Berlandier, who had also procured its eggs. A single specimen of this Owl was obtained by Mr. A. Schott in Texas, and Mr. Dresser also obtained two small Owls which he doubtfully refers to this variety,—one near San Antonio, and the other in Bandera County. Lieutenant Bendire writes that it is quite common in the vicinity of Tucson, Arizona, though Dr. Coues did not meet with it. Dr. Kennerly observed it on Bill Williams Fork, in New Mexico. It was there found living in the large _Cereus giganteus_ so common in that region, where it occupied the deserted holes of various kinds of Woodpeckers. It rarely made its appearance during the day, and then only to show its head from the hole, ready at any moment to disappear at the approach of danger. On one occasion it was observed among some very thick bushes near the water. It does not appear to have been met with by Dr. Cooper in California, where he refers all the Owls of this genus to the common _asio_. A single individual, referred doubtfully to this bird, was taken by Mr. Skinner in Guatemala. The eggs of this bird, taken in Tamaulipas by Dr. Berlandier, are of nearly globular shape, of a clear, almost crystal-white color, and measure 1.13 inches in length by 0.93 of an inch in breadth. As compared with the eggs of _Scops asio_ they are much smaller, their relative capacity being only as five to eight. The eggs of the var. _asio_ vary greatly in size according to their locality. Those taken in Florida are so much smaller than those from Massachusetts as almost to be suggestive of specific differences. An egg from Hudson, Mass., taken by Mr. Jillson in April, 1870, measures 1.50 by 1.30 inches, while one from Monticello, Fla., taken by Mr. Samuel Pasco, measures 1.30 by 1.15 inches. Mr. T. H. Jackson, of Westchester, Penn., informs me that he has found a nest of this Owl containing six fresh eggs, on the 5th of April.