46 
INTRODUCTION. 
consent, been placed at the beginning of the class 
Aves, and following out our plan, we propose to 
devote the present volume to that which has, in 
like manner, been placed second, or next to it. 
The Incessorial order of birds is by far the 
most important in the whole circle or chain, 
whether viewed in a scientific light, or taken in 
relation to its economy in the great plan of 
nature. In extent it is the most numerous, nearly 
equalling the numbers of all the others collec- 
tively ; consequently may be expected to contain 
an almost endless variety of forms, and modifica- 
tion of structure ; and thus it has been considered 
the typical order, or that in which the greatest 
united perfection of all the properties of a bird 
were combined. As the name indicates, the 
power of grasping and of perching, is a prominent 
feature in their form ; all possess the hallux, or 
hind toe, but in none are the claws retractile, as 
among the members of the former order. The 
habitual residence of the greater proportion is in 
the woods or thickets ; and the powers of flight 
are in all perfect, and in many very highly 
developed. Their food is nearly as varied as 
their structure ; but this is never seized by the 
feet, nor, with a very few exceptions, is the 
devouring of it assisted by these members. 
While the bill wants the form of a “ tooth,” which 
characterizes the typical raptores, and in those 
which here represent them by their partially 
predatorial habits, it is modified by the appear- 
ance which we express by the term “ notched.” 
