114 PAS&ERES. 



sionally kill birds ; Fissirostres (open bills), in which 

 the mandibles do not shut close for their whole 

 length, which are chiefly insect-feeders, and catch 

 their prey by hawking on the wing ; Conirostres 

 (conical bills), which have the bill more or less 

 enlarged at the base, and tapering to the point, 

 which are more miscellaneous in their feeding, but 

 differing so much in their characters and habits, 

 that no one can be selected properly descriptive of 

 the whole tribe ; Tenuirostres (slender bills), which 

 feed much on larvae, and other small animals in the 

 soft state, but catch them in such different situations 

 and ways, that they can hardly be said to have one 

 ver}" striking character in common ; and Syndactyles 

 (united toes), which agree in that structure of the 

 feet, and in several characters, though they differ in 

 others. 



That the last of these tribes or subdivisions of the 

 order is founded upon the structure of the feet, and 

 all the others upon that of the bills, is of itself suf- 

 ficient to show that the\" cannot be very accurately 

 descriptive of the birds. 



Dentirostres is far from accurate, because the birds 

 have a notch in the bill rather than a tooth, and 

 the bill is feeble. The falcons are the true den- 

 tirostres, the tooth in the bill being one of their lead- 

 ing characters, and they are the most typical birds 

 in the order accipitres. Besides, these birds are not 

 the only ones which have a notch in the bill, for 

 some of the divers, and other fishing birds, that have 

 not the tomia of the bill serrated, for the prehension 

 of their slippery prey, have it notched towards the 

 tip. This subdivision of the order contains birds so 

 different, both in appearance and in habit, that it 

 does not admit of much useful general description ; 



