332 



LIFE HISTORIES OF NORTH AMERICAN BIRDS. 



The eggs vary from tlircc to six in number. Sots of five are most often 

 found, Mini occasionally one may contain seven. Six is the largest number 

 I have personally found. They are pure white in color and oval in shape, 

 and the shell is smooth, finely granulated, and rather glossy. 



The average measurement of one hundred and three specimens in the U". S. 

 National .Museum collection is 40 by 32.") millimetres, the largest egg meas- 

 uring 4.'5. f> by 33.5, the smallest 37.5 by 31 millimetres. 



The type specimen, No. 20615 (PI. 12, Fig. 2), selected from a set of five 

 ,Mnr S from the Bendire collection, was taken by me on March 16, 1882, near 

 Fort Walla Walla, Washington. This is the earliest date on which I have 

 found eggs of this species; and incubation had already begun. 



113. Asio accipitrinus (PALLAS). 



SHORT-EARED OWL. 



.S7/-/.C accipitrina PALLAS, Reise, Russischen Reichs., i, 1771, 455. 

 .l.s/r; urcipitrinus NEWTON and YARROW, British Birds, ed. 4, I, 1872, 163. 



(B 52, C 321, R 396, C 473, U 367.) 



GEOGRAPHICAL RANGE : Entire western hemisphere, except Galapagos and part 

 of the West Indies ; also nearly throughout the eastern hemisphere, excepting Aus- 

 trulia, etc. 



The breeding range of the Short-eared Owl within our borders extends, 

 as far as known at present, throughout the middle portions of the United States 

 from about latitude 39 northward through the Dominion of Canada to the 

 Arctic regions, where Mr. R. MacFarlane met with it quite commonly in the 

 Anderson River country up to latitude 69. 



On the Pacific coast it is known to breed from southern Oregon, in the 

 vicinity of Camp Harney, about latitude 42, through Washington, Idaho, and 

 British Columbia to northern Alaska; and it is not improbable that it may 

 sometimes breed in California and Nevada. 



In the northern portions of its range it is only a summer visitor, migrating 

 south in winter. It is more than likely that it breeds, occasionally at least, in 

 suitable localities along the borders of the extensive marshes on the seacoast of 

 the South Atlantic States. By far the greater number of these birds, however, 

 breed north of our borders. 



In its general habits, the Short-eared Owl differs considerably from most of 

 the other members of this family found with us, in being not nearly so noctur- 

 nal and in frequenting the more open country, for while most of our Owls 

 inhabit limbered regions, this species shuns such sections and rarely even alights 

 on a tree. Its home is amidst the rank grasses or weeds usually found along the 

 borders of lakes and sloughs in the open prairie country, where it hides during 

 bright sunshiny days. If the sky is clouded, this Owl may be frequently seen 

 hunting in the early morning or evening and sometimes in the middle of the 

 day, and at such times it Hies very low, not more than a few feet from the 



