130 DAVENPORT ACADEMY OF NATURAL SCIENCES. 



Genus MEGASCOPS Kali-. 

 [B 49, part, R 402, C 465, U 373.] 



Megascops asio (Linn.). Screech Owl. Resident; common. Per- 

 haps the most familiar of our owls. The eggs are laid in April. 



Genus BUBO Cuvier. 

 [B 4 S, R 405, C 462, U 375-] 



Bubo virginianus (Gmel.). Great Horned Owl. Resident; com- 

 mon in the heavy timber bordering the streams. The eggs are laid 

 about the middle of February, and are usually two in number. Of 

 eight nests taken in the immediate vicinity of Des Moines, all con- 

 tained two eggs each, except one, which contained three. The young 

 are fledged by the first of May. The nest is usually a shallow depres- 

 sion in the bottom of a cavity of some tree ; or sometimes an aban- 

 doned hawk's nest is selected. An instance of the former nesting-site 

 was presented February 17, 1883, near Des Moines, the place selected 

 being a large sycamore tree. The cavity was about three feet in diam- 

 eter, and of about the same depth. There were three entrances, a 

 small and narrow one at the top, and two circular ones at the side, the 

 depression containing the eggs being near one of these lateral open- 

 ings. The bottom of the cavity consisted of decayed wood, which was 

 nearly hidden by snow. Scattered around were a dozen or more tail 

 feathers of the owls; the skull, several bones and bits of fur of a rabbit; 

 the leg of some large raptorial bird, and the remains of several smaller 

 birds besides a recently-captured pigeon. 



The great horned owl occupies the same nest year after year, and 

 even if the nest be disturbed and the first set of eggs taken, often de- 

 posits a second set in the same nest. A pair of young, just about to 

 leave the nest was taken on May 2, 1882, and kept for three years con- 

 fined in a barn. About the middle of June the "horns" began to ap- 

 pear, and in three or fonr weeks were quite conspicuous. These birds 

 were fed on fresh beef and rats — the latter they usually captured. 



[B 48, part, R 405 a, part, C 463, part, U 375 a.~] 

 Bubo virginianus subarcticus (Hoy). Western Horned Owl. 

 Rather rare. Occasionally taken in the northern part of the State. 



Genus NYCTEA Stephens 

 [B 61, R 406, C 479, U 376.] 

 Nyctea nyctea (Linn.). Snowy Owl. Rather rare winter visitant 

 in central and southern Iowa; more common in the northern part of 

 the State, where it is found only on the prairies. 



