INSESSORES. 



ORDER II. ^THE PERCHING BIRDS. 



The designation which discriminates the second order into whicli birds are classitied 

 has been selected to indicate a point of resemblance which obtains among them in the 

 absence of any more marked characteristics. The ground for associating them together 

 is, indeed, rather of a negative kind, comprehending those birds which arc neither 

 swimmers, nor waders, nor climbers, nor rapacious, nor gallinaceous ; yet among which 

 may be traced a general similarity of structure, and especially such an insensible merging 

 of one group into another, that it is difficult to arrange them into rigid subdivisions. 

 ^Vithout having the ferocity of appetite which we have seen to characterise the Acci- 

 piTRES, they are not, on the other hand, restricted, like the gallinaceous birds, to a 

 regimen of grain and vegetables ; but, in accordance with varied modifications of the 

 beak and of the digestive organs, they feed upon insects, fruit, and grain, or upon all 

 combined. Some, however, which possess a tolerably strong bill, are even found to pursue 

 small birds. 



Their stomach is in the form of a muscular gizzard. As among them are the singing- 

 birds, the most complicated conformations of the lower larynx are apparent. The 

 proportional length of their wings, and the extent of their flight, are as variable as their 

 mode of life. Their sternum has usually but one slope on each side at its lower edge ; 

 but there are two in some birds of this order. 



In consequence of the diversity of members of this order, and the difference in 

 many important respects between them, it has been found necessary to subdivide them 

 into primary sections or tribes, in order to avoid the inevitable confusion which would 

 otherwise follow. These are four in number, and have been designated as follows : — 

 1, FiisiROSTRES ; 2, Dentirostres ; 3, Conirostres ; 4, Tenuirostres ; each tribe being 

 further arranged into several families. 



TRIBE I. FISSIROSTRES. 



The designation of this tribe is derived from the width of gape of the bill possessed by 

 a considerable number of the birds of the Insessorial order. In combination with this 

 power of grasping their prey, they are also gifted with extraordinary powers of flight ; 

 so that with the utmost velocity of motion there is a tirelessness of wing which no effort 

 seems able to subdue. This capacity of flight is, indeed, an essential qualification, when 

 it is remembered that it is upon winged food that they have to obtain their subsistence, 

 in order to secure which great velocity is obviously necessary. 



The Family placed first in order under this tribe comprehends the Goatsuckers, which, 

 in some important respects, are intimately associated with some members of the Acci- 

 PITRES, which we have just left ; and may be remarked in passing as one of the 

 innumerable illustrations which are furnished of the gradational character of the works 

 of nature. To this we have now to advert. 



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