ORDER RODENTIA. 237 



teeth, which are capable, if brought into action, of inflict- 

 ing severe wounds, are equally unemployed with its nails, 

 in all purposes of warfare and self-defence. When seized, 

 it utters a sharp cry, makes some efforts to recover its 

 liberty, and to escape from the hand that holds it ; but it 

 is to this only that its efforts are limited. We should pro- 

 bably not find a second example of this extreme inoffen- 

 siveness in the whole class of Mammalia. Similar in- 

 stances in either of the lower classes would be rare. 



Notwithstanding, however, the extreme imbecility of the 

 individuals, the species maintains its existence ; for nature, 

 while she has left them an easy prey to creatures of a more 

 energetic character, has made them peculiarly prolific. 

 This, indeed, is very generally the case with all the weaker 

 animals, whose chances of premature destruction are so 

 much multiplied ; if the span of their existence is frequently 

 abridged, their means of reproduction are proportionally 

 increased, and the most complicated of the Creator's sub- 

 lunary works are thus preserved from those casualties which 

 might otherwise in some degree counteract the power that 

 called them into life. It may, indeed, be said that species 

 and genera, to an extent limited only by the powers of ima- 

 gination, have existed and perished by casualties, or the 

 want of sufficient powers successfully to contend for their 

 preservation ; and that there are others, as the animal in 

 question, whose powers are nearly balanced by its casualties, 

 though the former prevail. 



Were this hypothesis, however, correct, there can now 

 scarcely remain a doubt that facts would have been brought 

 to light to support and confirm it. Philosophy has pene- 

 trated the bowels of the earth, and man's insatiable appe- 

 tite for knowledge and discovery has revelled in the artifi- 

 cial mine as well as in the natural cavern. Facts have ac- 

 cumulated upon facts in geological science, destructive of 

 preconceived notions as to the theory of the earth and of 



Vol. III. S 



