214 THE TOWER MENAGERIE. 
the different races; by the great extent of dilatation of 
which their pupils are capable, a provision admirably 
calculated for enabling them to see by night; by the 
breadth and apparent bulk of their heads and _ bodies, 
both of which are thickly clothed with long and _ soft 
feathers; by the plumage of their legs, which in all the 
European species is continued down to the very toes, 
and sometimes even along them; by the direction of 
their toes, which are all naturally turned forwards, the 
external one being, however, capable of taking an oppo- 
site direction ; and by the high degree of retractility and 
sharpness of their claws. 
All these birds were comprehended by Linneus under 
the generic name of Strix, but later naturalists have sub- 
divided them into several genera, dependent on the size 
of the ears and of the ocular discs, on the presence or 
absence of two remarkable tufts of feathers on the head 
having somewhat the appearance of horns, and on the 
covering of the legs and feet. The Virginian Horned 
Owl is spread over nearly the whole continent of Ame- 
rica from north to south. Its plumage is brown above, 
marked with numerous transverse black stripes, and the 
feathers of the under surface are of a dirty white, trans- 
versely striped with blackish-brown. 
os uaa 
voi a 
iy 
| 
