76 NORTH AMERICAN OOLOGY. PART I. 



extremity of the hole. The eggs are uniformly four in number, pale white, and 

 about the size of those of the common House Pigeon, the great end, however, being 

 remarkably large, and tapering abruptly. 



Dr. Heermann's account, describing individuals met with in California, differs 

 somewhat from the above. He speaks of the nest as composed of a few straws 

 placed at the end of a winding burrow, varying from four to ten feet in length, and 

 the eggs as four in number, pure white, and nearly spherical. Dr. Gambel, who 

 also observed this bird in California, states that he has occasionally found the bird 

 in solitary burrows, and also that it often makes use of the holes dug by the large 

 ground-squirrel (Sperniophilus beecheyi"), which is there a very common species. 

 The Owls often dig their own burrows, and live in scattered companies of four or 

 five. Dr. Gambel also states that the bird is a resident of California throughout 

 the year. Dr. Woodhouse found it abundant west of the Arkansas River, and no- 

 ticed that, though he often found the Owl and Marmot together, he also frequently 

 met with them separately, the Marmots where there was apparently no water, the 

 Owls always in the vicinity of water. He frequently found the latter in villages 

 by themselves. On being approached, they commenced chattering and bowing, pre- 

 senting quite a ludicrous appearance. 



Mr. Darwin, in the Zoology of the Beagle, met with the A. cunicularia, a larger 

 species, in crossing the Pampas of South America. In Banda Oriental, he says, it 

 is its own workman, and excavates its burrows on any level spot of sandy soil, but 

 in the Pampas, or wherever the Bizcacha is found, it uses those made by that ani- 

 mal. This bird, he states, preys on mice and reptiles, the North American bird on 

 insects. Lieutenant Gilliss gives a similar account of it, from observations made 

 in Chile. The egg of this Owl is slightly oblong and somewhat more pointed at 

 one end, differing in this from the eggs of most Owls. It measures l T 6 g inches in 

 length by l T 2 g in breadth. Its color is clear and uniform white. 



Since the above was prepared, my esteemed young friend, Mr. Nathaniel H. Bishop, 

 of Medford, Mass., has kindly furnished me with the following interesting account of 

 his observations on the habits of the A. cunicularia. They were made by him 

 during his adventurous journey across the Pampas of South America. Although 

 the cunicularia is not a North American bird, his notes are appropriate here as 

 affording an interesting comparison between the habits of two very closely allied 

 species. 



" I first met with the bird on the banks of the river San Juan, in Banda Ori- 

 ental, one hundred and twenty miles west of Montevideo, where a few pairs were 

 seen, devouring mice and insects. From the San Juan, travelling westward, thirty 

 miles, I did not meet with a single individual ; but after crossing the River Las 

 Vacas, and coming upon a sandy waste covered with scattered trees and low bushes, 

 I again met with several. 



" Upon the Pampas of the Argentine Republic they are found in great numbers, 

 from a few miles west of Rosario, which lies on the Parana, in latitude 32 56' south, 

 long. 60 32' west, to the vicinity of San Luis, where the Pampas end and the Trave- 

 sia or desert commences. On these immense plains of grass it lives in company 



