368 Mr. Vigors's Sketches in Ornithologi/. 



Art. XLIV. Sketches in Ornithologi/ ; or, Observations 

 on the leading Affinities of some of the more extensive 

 groups of Birds. Bi/ N. A. Vigors, jun. Esq. A.M. 

 F.L.S. 



(Continued from p. 197.) 

 OX THE GUOUPS OF THE VULTURID^. 



The mode in which Nature regulates the numbers of the animal 

 kingdom according to size, restraining those of the larger subjects 

 within moderate limits, and compensating by the multitude of the 

 smaller for their inferiority in bulk, is too generally observable to 

 need more than a mere reference to the fact. In those depart- 

 ments of Zoology, it is true, which comprise the animals that are 

 chiefly necessary to man's support, such as the Herbivorous Mam- 

 malia, and the Gallinaceous Birds, some modification of this 

 general law takes place. Here the peculiar fecundity bestowed 

 upon some species, and the facility of domestication in all, renders 

 their powers of production more extensive ; and although the 

 .variety of forms in such groups is diminished in the inverse ratio 

 of their size, yet the number of individuals may be so far multi- 

 plied as to answer all the conveniences and supply all the wants of 

 man. A.mong those animals, however, whose business it is to 

 restrain the luxuriance of nature, either in the animal or vegetable 

 world, and either in its living or decaying state; whose work in 

 fact is a work of destruction — themselves the agents of prey, 

 more than the objects of prey to others — the general law prevails 

 without any reserve or modification. Thus in these predacious 

 animals the variety of forms among the larger tribes is universally 

 found to be limited ; the species are few ; and the individuals not 

 numerous. While on the other hand where the dimensions of 

 these animals are small, the multitude of forms, of species, and of 

 Individuals, is without any apparent limits. By their overpower- 

 ing numbers they supply the inefficiency of their individual labours ; 

 in silence and in secrecy they pursue their work of destruction ; 

 and their unobtrusive agency is perceptible only in the magnitude 

 of the effects which they produce. 



