26 BIRDS OF IVIGTUT. 



tried to catch a Pigeon that was sitting on the roof of the 

 liouse, but always in vain. On the other hand the Falcons 

 themselves were at times worried by Ravens, but neither 

 party seemed ever to be in real earnest. 



Once a Falcon was attracted by the report of my gun as I 

 shot a Ptarmigan, and I brought him within shot-range by 

 throwing the dead Ptarmigan into the air. At another time 

 I observed a white Falcon sitting at some distance from a 

 dark Falcon, that was making his repast on a sea-fowl, and 

 ffhen the dark Falcon flew away with his prey the white one 

 followed, evidently hoping to obtain a portion. 



I have at various times heard these birds utter s6mewhat 

 weak and tremulous cries, resembling sounds I have heard 

 from Falco tinnunculus. 



In summer the present species is less frequently seen 

 near the settlements in the vicinity of Ivigtut ; but it nests 

 nevertjieless in the neighborhood of the " bird-cliff." On 

 the 3d of June, 1886, there was shot a dark Falcon, with a 

 naked spot on the ventral side, and in its stomach were 

 found the remains of a Ptarmigan. 



From Frederickshaab I obtained a set of eggs said to 

 have been gathered on the 16th of April, while the grdund 

 was under a mantle of snow. 



Measured transversely, the white and the gray Falcons 

 are of about the same size ; namely, 59 to 60 cm. long, on 

 the average. The largest I measured was 62 cm. long and 

 133 cm. broad, and weighed 1.8 kilogram. The smallest, 

 a gray specimen, was 51.5 cm. long, 102 cm. broad, and 

 weighed 0.9. kilogram ; and a white bird measured about 

 the same length. 



[The observations recorded here suggest that the gray * 

 and white forms of the Greenland Gyrfalcons are merely 

 individual differences, — phases of plumage, — instead of 



