5S British Birds, with their Nests and Eggs. 



assistance indicated. When in capti\ity mam- of the species never seem to 

 require water either to drink or to bathe in. 



The food of Owls consists of rats, mice, voles, moles, bats, small birds, 

 large moths and beetles, earth-worms, frogs, and fish. The larger Owls, such 

 as the Snowy and Eagle Owls, devour, in addition to this dietan,-, fawns, hares, 

 rabbits, squirrels, grouse, and other winged game. 



Owls moult but once in a 3'ear, and are in their best plumage during 

 the winter ; their feathers do not possess an}- after shafts, as in the Falconidte. 

 In colour their plvimage is general!}- brown, or reddish bro\sTi, mottled, barred, 

 or vermiculated with various shades of brown, black, and gre}-, thus corres- 

 ponding with the tints of their surroundings in the bark and trunks of trees, 

 &;c., and is protective, serving to conceal them from the notice of their pre}-. 

 The male is smaller than the female, and there is, in general, no difference 

 in the plumage of the sexes. Although Owls have the appearance of being 

 large birds this is chiefly due to their mass of soft plumage : when the}- are 

 handled it is at once discovered that their bodies are small in proportion to 

 their apparent bulk, and that they are made up chiefly of feathers. 



The genera of Owls on the British list may be tabulated as follows : — 



I. — Owls that have an operculum to their ear cavities ; these Owls are almost 

 exclusively nocturnal. 



Strix, Linnaus. — Facial disk large and complete, narrowing rapidly below the 

 eyes towards the beak. Legs long, and clothed with downy feathers 

 to the origin of the toes, which are covered above with a few 

 bristle-like feathers ; hind toe reversible .: claw of the middle toe 

 serrated on the inner edge. 



Asio, Brisson. — Facial disk complete. Auditor}- opening asymmetrical. Legs 

 and toes feathered to the claws. Two tufts of feathers on the head 

 more or less elongated. 



Syrnium, Savigny. — Facial disk large and complete. Head large and rounded. 

 Legs and toes feathered. 



NycTALA, C. L. Brelwi. — ^Facial disk large and nearly complete. Legs and toes 

 thickly feathered. Auditor}- opening as}-mmetrical, the bones of the 

 skull affected and differing on either side. 



II. — Owls that are without an operculum to their ear ca^-ities ; these Owls are 



either entirely or partially diurnal. 

 ATHE>rE, F. Bok. — Facial disk not well defined. Legs long, covered with short 

 feathers ; toes covered above with bristles. 



