STRIX. 



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operculum. In their habits they scarcely differ from other Owls. Their 

 eggs are pure white. This genus contains about forty species, which are 

 distributed all over the world, except in the Australian region ; and even 

 here one species has found its way to the Sandwich Islands. Seven species 

 are found in Europe, of which four have occurred in Great Britain. The 

 "Wood-Owls may be divided into subgenera, either on the presence or 

 absence of ear-tufts or on the character of the markings of the underparts 

 in some the transverse bars being principally developed, and in others 

 the longitudinal stripes. The first characters are those usually adopted, 

 but the latter are probably the most important. 



