154 STRIGID^. 



Holland, and that a young bird, which made its appear- 

 ance in the winter of 1802. As in the adult Gyr-Falcon, 

 already described, the ground colour of the plumage in 

 the adult Snowy Owl is pure white, more or less spotted 

 and barred with dark umber brown, according to the age 

 of the individual ; these dark marks becoming smaller 

 every succeeding year, until in very old individuals from 

 high northern latitudes the whole plumage becomes pure 

 white, without any spots whatever. The brown mark 

 when present is situated towards the end of the feather ; 

 and upon the feathers of the under surface these markings 

 are semilunar in shape, while those on the feathers cover- 

 ing the back and wings are more linear. The feathers 

 forming the incomplete facial disk, those of the upper 

 part of the breast, and also the downy feathers defending 

 the legs and toes, are pure white ; the beak and claws are 

 black; both are partially hidden by feathers; the latter 

 are long, curved, and very sharp. The irides are bright 

 orange yellow. The whole length of the Snowy Owl is 

 from twenty-two to twenty-seven inches, the difference de- 

 pending on the sex : the females are much the larger of the 

 two. M. Temminck says the young birds are covered with 

 brown down, and their first feathers are also light brown. 

 The vignette below represents the crystalline lens and 

 the bony ring of the eye in this bird, which may be com- 

 pared with those of the Eagle at page 19, and both are 

 referred to at page 15. 



