ACCIPITRES. 



1G3 



again excepted] pursue other Birds ; their flight accordingly is mostly powerful. The 

 greater numher still retain a slight web betwixt their external toes. 



The Passerine Birds comprise many more species than all the other families ; but 

 their organization presents so many analogies that they cannot be separated, although 

 they vary very much in size and strength. Tbeir two external toes are joined at the 

 base, and sometimes higher. 



Finally, the name of Climbers is applied to those Birds in which the external toe is 

 directed backwards like the thumb, because the greater number of them [some of them] 

 avail themselves of a conformation so favourable for a vertical position, to climb along 

 the trunks of trees.* [As constituted upon this single character, the present group is 

 a most unnatural one, excluding genera that in every other respect belong to it, and 

 including the Parrots, which differ widely from the rest in every other detail of their 

 conformation. Besides the Parrots, also, which are the only true climbers among 

 Birds, (if we except perhaps the Colies,) the Woodpecker and Barbet groups comprise 

 all the yoke-footed species which ascend the trunks of trees, the latter only being 

 enabled to descend them ; and corresponding genera to these occur among the Passerine 

 Birds, as the Creepers and their allies — to the Woodpeckers, and the Nuthatches — to 

 the Barbets. The Trogons moreover, as stated at p. 156, are yoke-footed on a different 

 principle from the rest. We have no hesitation in placing the Parrots at the head of 

 the whole series of the class of Birds.] 



Each of these orders subdivides into families and genera, principally after the con- 

 formation of the beak. But these different groups pass into each other by almost 

 imperceptible gradations, insomuch that there is no other class in which the genera 

 and subgenera are so difficult of limitation. 



THE FIRST ORDER OF BIRDS,— 



THE BIRDS OF PREY (ACCIPITRES, Lin.)— 



Are recognized by their hooked beak and talons, — powerful weapons, with which they immo- 

 late other Birds, and even the weaker Quadrupeds and Reptiles. They are among Birds what 

 the Carnivora are among Quadrupeds. t The muscles of their thighs and legs indicate the 

 force of their claws ; their tarsi are rarely elongated : they having all four toes ; and the claw 

 of the thumb and that of the innermost toe are the strongest. 



They constitute two families, the Diurnal and the Nocturnal. 



The Diurnal Bikus of Puey have the eyes directed sideways; a membrane, termed the 

 cere [as in the Parrots], covering the base of the beak, in which the nostrils are pierced ; three 

 toes before [the outer in the Osprey genus reversible], and one behind, unfeathered, the two 

 exterior almost always connected at base by a short membrane; the plumage close, the quills 

 strong, and flight powerful. [They have constantly a large craw (tig. 71) or dilatation of the 

 gullet]; their stomach is almost wholly membranous; their intestines [save in the Osprey 



genus] but httle extended, and furnished with minute coeca. The sternum (fig. 72) is large 

 and completely ossified, [or with only a posterior foramen left, in most of the genera], ■ 

 order to give more extended attachment to the muscles of the wing; and their fourchette 



• In my first ff/fmnfffdlf Skftrh, in 1790, I « ■»< "Mii;'''! 10 lapprou 



the ontci Picm of L ca^wbicbhu i do determinate cbw 



[«t lout »> CODitllUlod l>)' that niituraliit J. M. IUigcr,iuU the majority 



nf recent Oraltuoloftata, ba*o UMntod i" thi« tuppreitnm. 



t Afl the fraglvoiDOJ Pftrrota may bo compovtd tu the (jnadruu 

 -V.o. 



M 2 



