292 



NATURAL HISTORY OF BIRDS. 



a precipitous mud-bank on the border of a stream or lake. The eggs vary in number 

 from three to five, and are of a creamy-white color, sometimes with faint and obscure 

 darker blotches, usually qiiite heavily marked with spots and dashes of brown. 



The last group of this sub-family which we shall take up is the genus Buteo, 

 which includes the true buzzards, the number of which varies according to the esti- 

 mates of different authorities as to varieties and geographical races. Probably there 

 are at least twenty-five well-marked species distributed in all parts of the world, 

 except Australia, and perhaps half this number are found in America. 



The common ' hen-hawks ' (Buteo borealis and J?. lineatus) of the eastern United 

 States are familiar examples of the genus, and represent about the average size. Their 



FIG. 137. Buteo vulgarly, common buzzard. 



habits are too well known to need extended description, and they may "be seen, sum- 

 mer or winter, sweeping in graceful curves over the country, rising and falling in 

 spirals, unless after noting prey, when they sometimes dart down hundreds of yards in 

 a very few seconds. Although they feed much on birds and rabbits, and are frequent 

 visitors to the farm-yard, they seem to have a special predilection for squirrels ; and 

 in regions extensively wooded with pines, where the red-squirrel is most abundant, 

 these noisy little rodents must form a large part of the Buteo's food. 



Probably the white-tailed buzzard, J3. pterocles (albocaudatus) of South America 

 represents nearly the maximum size in the genus, its length being about two feet, the 

 wing eighteen and one half inches, and tail seven ; but females of the African and 

 Himalayan B. ferox, which is not uncommon in south-eastern Europe, sometimes 



