154 ZOOLOGICAL GARDENS. 



teaches us that they are in reality the best and most 

 efficient protectors of our corn-fields and granaries from 

 the devastating pillage of the swarms of mice and other 

 small rodents, which but for them would increase to 

 the most mischievous extent. By their wholesale de- 

 struction of these petty but dangerous enemies, the 

 Owls earn an unquestionable title to be regarded as 

 among the most active of the friends of man; a title 

 which only one or two among them occasionally forfeit 

 by their aggressions on his defenceless poultry. 



These birds are separated from all the rest of the 

 Raptorial Order by external characters as remarkable 

 as their habits. In the system of Linnseus they consti- 

 tuted but a single genus, which has now, like the 

 majority of the groups formed or adopted by that great 

 master of natural science, been converted into a family, 

 and subdivided into several minor sections, each distin- 

 guished by its own generic appellation. The entire 

 family are characterized by the comparatively large size 

 and globular form of their head ; the magnitude of their 

 eyes, which are directed forwards, surrounded by a 

 broad disc of slender feathers, and furnished with 

 pupils dilatable to a very great; extent and capable of 

 powerful contraction ; the curvature of their beak from 

 its very base, and the almost complete immersion of 

 that organ in the straight bristly feathers that clothe 

 the soft and spungy cere; the extent of their gape; 

 the shortness and thickness of their neck ; the versa- 

 tility of the outer toe, which is equally capable of being 

 directed forwards or backwards ; the extreme retrac- 

 tility, strong curvature, and acuteness of their talons ; 

 and the great apparent bulk of their bodies, in conse- 

 quence of the thickness of the puffy plumage with 

 which they are invested in every part. Their powers 

 of flight are not great; for although their wings are 



