NATURAL HISTORY. 



355 



" Cease, then, nor order imperfection name : 

 Our proper bliss depends on what we blame." POPE. 



The web of the spider is a beautiful contrivance, evidently designed to ensnare flies. 

 The scent by which the stoat pursues the rabbit ; the teeth with which the former 

 perforates the neck of its victim, and the instinct which guides it to attack the 

 neck, are three special means bestowed for a given end. The gaping mouths of 

 swallows and night-jars are manifestly conceived for the purpose of capturimg 

 insects in the most certain manner. Although man is born the most defenceless of 

 all creatures, there is not a single animal gifted with an instinct to pursue him t 

 and armed with weapons adapted to give effect to that instinct. The elephant, the 

 lion, and the tiger, although endowed with strength by which they could imme- 

 diately crush him, all retire from and avoid his presence, unless he trespasses upon 

 their haunts, or they are driven to extremities of rage or hunger by restraints which 

 he imposes upon them. Regarded as enemies to man, their armatures are too 

 formidable : the tusks of the elephant, and the talons or teeth of the lion and tiger, 

 might be dispensed with, and they would still be immensely his superiors in the 

 balance of natural powers. Even the vermin that sometimes surround and annoy 

 man, are the enemies of his negligence and vices, and not of himself. On the 

 contrary, the whole of the animal creation, in some form or other, aie friends of 

 man, and contributors to his need. 



1155. TABLE OF THE FECUNDITY OF VARIOUS ANIMALS. 



In five generations one aphis may produce 5,000,000,000, and there are 20 

 generations in a year. The numbers are beyond calculation. 



1156. Why does the duration of life of different 

 greatly vary ? 



The longevity of animal races appears to be in the inverse 

 ratio of their fecundity. The wisdom of this arrangement i 



