28 PASSERES. 



ORDER II. PASSERES. 



(Percliing Birds.} 



THOUGH for the most part the birds of this 

 Order are of smaller size than those of the others, 

 yet the immense number of species included in it, 

 which is about equal to that of all others together, 

 renders it the most important of all. It is also 

 considered by naturalists as the most typical ; that 

 is, as displaying the properties which distinguish 

 a bird from other animals, developed in the great- 

 est perfection. Great varieties of form and struc- 

 ture are found in a group so immense as this ; so 

 that but few positive characters can be assigned 

 which are at the same time common to the whole, 

 and peculiar to them. The power of grasping 

 the branches and twigs of trees with the feet, and 

 the habit of perching upon these, are prominent 

 in the Order ; the hind toe is always present, and 

 the claws are not capable of being elevated, as in 

 the birds of prey. The greater number of the 

 species habitually dwell in woods and thickets. 

 The power of flight exists throughout the Order 

 in full perfection, and in some of its genera, as 

 the Swifts and the Humming-birds, may be con- 

 sidered as at its greatest development. The beak 

 varies greatly in form, but its general shape is 

 that of a cone, more or less lengthened. In some 

 of the genera which retain predaceous propensi- 

 ties, a trace of the tooth .which marks the upper 



