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truly surprising. All the Owl tribe are mousers. A Pine-tree, 

 spreading and thick-set, near my house, affords a shelter and 

 roost to about a dozen' of these Owls through the winter." He 

 therefore enjoyed the opportunity of witnessing their opera- 

 tions ; and a few of them, for they are generally gregarious, 

 will soon, in his opinion, clear the barn and out-houses of a 

 farm, as well as the fields, from vermin, in the vicinity of their 

 resort. Farmers, he said, should encoui-age the small Owls to 

 reside near their buildings, and invite their visits in eveiy way, 

 for it is only the larger species that will attack poultry, or com- 

 mit damages of any sort. 



TJic different habits of foraging that distinguish the several 

 tribes and species of the feathered race, deserve attention, as 

 indications of a corresponding difference in the character of 

 their food. Those, for example, that seek their food chiefly 

 from the surface of the ground, would forage in a different 

 manner from those species that collect it from under the sur- 

 face. The Swallows, that catch all their food while on the 

 wing, give proof by this habit that they pursue only winged 

 insects ; but their habits of foraging differ very essentially from 

 those of the Pewees, who also catch all their food while on the 

 wing. The Robin and the Red-winged Black-bird take their 

 food enthely from the ground ; but their ways, while seeking 

 it, are very different. Their respective habits of foraging are 

 adapted to the successful pursuit of the worms and insects that 

 constitute their princijjal food ; for although each of these birds 

 will devour the same kind of insects that come in their way, 

 they make certain kinds, respectively, the chief objects of their 

 pursuit. It is necessary to study all the different habits of 

 foraging, that mark the several species, in order fully to com- 

 prehend the principle "which I wish to inculcate, — that each 

 S2)ccies of bird performs certain services in the economy of -nature, 

 ivhich cannot he so xcell accomplished by any other species, — and" 

 that it is necessary, therefore, for this end, to preserve them 

 all in their due proportions ; that is, in such proportions as 

 would spontaneously exist, if the whole race Avere unmolcst- 



