184 ECONOMIC MAMMALOGY 



and its possible status as a source of meat, fur or other useful commodi- 

 ties. All this requires an extensive and accurate knowledge of natural 

 history, common sense, good judgment, open mind and conscientious 

 devotion to truth. 



Another difficulty that must be squarely faced is that, unless one 

 be constantly on guard and fully informed, the contents of the stomachs 

 may be misleading as to the habits of their former possessors. Certain 

 predatory animals are also scavengers, and feed upon carcasses of ani- 

 mals they have found already dead. Thus the hair of a horse or cow 

 or the wool of sheep may be found in the stomach of a coyote, which 

 would not necessarily prove that it killed the sheep, and almost cer- 

 tainly would not prove that it killed the horse or cow. All evidence in 

 scientific investigations should be carefully scrutinized and used with 

 sound discretion. 



