that connect the Orders and Families of Birds. 409 



it at some distance from the Owls, in which the same members 

 are comparatively strong ; while the wide gape of its mouth serves 

 to divide the families still further*. A connecting link has been 

 however supplied by an Australasian group, the Podargus of 

 M. Cuvier, which harmonizes these discrepant characters. We 

 have an opportunity of observing among the specimens in the 

 collection of the Society, how far the bill of this extraordinary 

 genus combines the different forms of that of the two genera, and 

 how far the legs, still maintaining the characteristics of Caprimul- 

 gus, such as the unequal length of the toes, are related to those of 

 Striv by their superior robustness. Here, indeed, there is a beau- 

 tiful gradation of affinities. All the front toes of Caprimulgus are 

 united by a connecting membrane as far as to the first joint : those 

 of Strix are divided to the origin ; while those of Podargus par- 

 take of the characters of both, in having the middle toe connected 



_. ('ill 



which the serration can be applied. There are many other groups of birds, possessing 

 the same character, to which the same appUcation of it can never be assigned. We 

 may observe, for instance, that the greater part of the genus Pelecanus of Linnasus pos- 

 sess this character. This group of the Natatores meets the Birds of Prey, as we shall 

 have occasion to observe hereafter, on the opposite side of that circle which embraces 

 the whole class : and thus on both sides of the order we find a similar construction 

 in the groups immediately approaching it. Many of these birds, whose feet are natu- 

 rally ill adapted by their webbed structure for laying hold of any object, are yet found 

 to incubate among trees, where the serrated claw may give them a firmer power of 

 prehension : they are also asserted to seize their prey occasionally by the foot ; in 

 which act the structure of the nail, as in the case cited from Mr. White respecting 

 the Caprimulgus, maybe peculiarly useful. — See p. 418. Notes * and f. The family 

 of Ardeide among the Wading Birds equally exhibit an analogous construction in 

 the middle nail. Here, again, this character seems adapted to their mode of life in 

 enabling them to hold their prey more firmly in those slimy and muddy situations 

 where it might otherwise elude them : while, at the same time, it may assist their feet, 

 (which, like those of the Pelecanida, are naturally ill suited for grasping,) in their hpld 

 among the trees, where, like some also of the latter family, they build their nests. ■ 



* " Rostro minimo nigro, Rictu oris ingcnti, Pedibus brevibus exilibus ab aliis qui- 

 buscunque Noctuis abunde distinguitur." Rati St/n. Av. p. 27- .;. ,j.„. 



with 



