8o THE BOOK OF NATURE STUDY 



it is proposed here to take the common sparrow as an object 

 lesson. 



This bird, it should be remarked, is a member of that great 

 group known as the " Passeres " or perching-birds. Ranging 

 in size from the tiny gold-crested wren, one of the smallest of 

 living birds, to the giant of the tribe, the raven, all agree in having 

 more numerous voice muscles than any other birds ; and they 

 have besides yet other anatomical characters in common, which 

 demand no reference here. But this much should be remarked. 

 All have relatively short legs, and the toes arranged on a model, 

 which shows that perching rather than walking is their primary 

 purpose. 



This great Passerine assemblage, which represents about one- 

 half of all the known birds that is to say, of the 13,000 species 

 which had been described, about 6000 are Passerine birds can be 

 split up into many groups; and of these the "finch-like" 

 birds form a very large proportion. To this finch group the 

 sparrow belongs ; and the main characteristic of this group is 

 the conical-shaped beak, the sheath of which is of considerable 

 hardness. Such a beak is admirably suited for picking up and 

 crushing seeds. And if a large series of finch-like birds is examined 

 a surprising range in size will be found, the hawfinches possess- 

 ing the largest of all ; these birds being able to crush seeds that 

 few other birds could manage. Thereby it should be noticed 

 they can continue to live in areas thickly populated by their 

 near relatives without adding to the struggle for existence, since 

 they are enabled to " tap " food supplies which their neighbours 

 must perforce leave untouched. 



In the matter of plumage the common sparrow presents some 

 extremely interesting points, and to properly appreciate these, 

 a comparison should be made with its near relative the tree-sparrow. 



In the first place, then, the sexes in the common sparrow 

 are dissimilar, the female being much more soberly clad than her 

 mate. The most striking features of the male are the black 

 throat and the rich mottling of russet and black on the upper 

 parts ; the crown of the head, it should be especially noticed, is 

 grey, bordered on each side by a band of russet ; while across 

 the wings runs a bar of white. 



