THE SNOWY OWL. 391 



to use its strong hinder parts. * * * The natives assert that when a 

 Ptarmigan is sighted, the Owl endeavors to start the bird into a run and is 

 then seized, though it adopts different tactics in this case; the prey is crushed 

 to the ground, the outspread wings of the captor preventing those of its prey 

 from allowing it to rise." 



The nests of the Snowy Owl are ordinarily placed- on the ground, usually 

 on the highest and driest point in the surrounding tundra. Occasionally a 

 nesting site on a rocky ledge or a cliff is chosen. In either case the nest is 

 but a flimsy affair at best, consisting, if on the ground, of a slight hollow 

 scratched out by the birds, and this is usually lined with a little moss and 

 a few feathers; if on top of a ledge or a cliff, the eggs frequently lie on 

 the bare rock, with just enough material around them to keep them in place 

 and prevent them from rolling about. Incubation begins with the first egg 

 laid, which are deposited at irregular intervals. Young birds are often found 

 in the same nest with nearly fresh eggs. Mr. Turner says that the old birds, 

 especially the female, are very fierce in the defense of their young. They fly 

 close to the head of the intruder with their talons fully spread and snapping 

 their mandibles. The natives in such instances seize one of the young and 

 make it struggle, which causes a charge of the parent on the intruder, who 

 holds up the stock of his gun and lets the bird dash against it, which usually 

 stops further action on their part. 



Fi'om tlu-ee to ten eggs are laid by this species, usually from five to seven. 

 Mr. Collett states that in 1871 he found as many as ten in several instances in 

 northern Norway. They are deposited about the latter part of May, and in its 

 extreme northern range not until June. All of the eggs of this species in the 

 U. S. National Museum collection appear to have been taken in June. Some of 

 these come from Labrador, others from Fort Churchill, Hudson Bay, latitude 

 59° N., a set of six from Repulse Bay, Melville Sound, Arctic America, lati- 

 tude 66° N., and a set of three from the Yukon Delta, Alaska. But one brood 

 is raised in a season. 



The eggs of the Snowy Owl are white in color, with a faintly perceptible 

 creamy tint in some instances, and oblong oval in shape. None of these eggs 

 are as round as those of the genus Btibo, and their shell is roughly granulated 

 and without luster. A few corrugated lines starting a trifle beyond the center 

 of the egg and running to the longer axis are noticeable in the majority of 

 specimens examined by me. 



The average measurement of fifteen specimens in the U. S. National Mu- 

 seum collection is 57 by 45 millimetres; the largest egg of the series measuring 

 60 by 47, the smallest 55 by 44 millimetres. 



The type specimen, No. 13041 (PI. 12, Fig. 19), selected from a set of six 

 eggs, was obtained by Capt. C. F. Hall, during his Arctic expedition in the 

 Polaris, in June, 1867, at Repulse Bay, Melville Sound, latitude 66° N., 

 while in search of the remains of Sir John Franklin's party. 



