210 THE REASON WHY: 



&quot; The miijra ion of birds from a hotter to a colder country, 

 or a c Ider to a hotter, according to the seasons of the year, as 

 their nature is, I know not how to give an account of it, it is 

 so strange and admirable.&quot; RAY. 



629. Wliy are certain species of animals destined to perform their 

 functions only periodically ? 



Because it has been allotted to them to check superfluities 

 and remove nuisances. 



&quot;When vegetation develops its vast powers of reproduction, there 

 issue forth from their winter retreats innumerable creatures that 

 live variously upon the roots, leaves, or seeds. 



When the vitality of vegetation diminishes, the natural office of 

 these creatures ends ; and they return again to their torpid 

 condition. 



During the season when animal existence is vigorous, and the 

 destinies of nature are being fulfilled, the great harvest of death 

 strews millions of bodies upon the face of nature. Then the 

 scavengers are busy day and night ; and either devour upon the 

 surface, or bury in the earth, those substances which would other 

 wise diffuse pestilential influences. 



630. Wliy do some portions of the animal creation migrate? 



For two reasons : first, the welfare of the migrating animal is 

 promoted by finding milder regions, and a continual supply of 

 food; second, the blessings of creation are thus diffused, by 

 seasonable visitations of creatures useful to man, to those localities 

 where he stands in need of them. 



631. Had the Creator so willed, all these animals might have been organised so as 

 not to require a warmer or colder climate for the breeding or rearing of their young ; 

 but His will was, that some of His best gifts should thus oscillate, as it were, 

 between two points, that the benefit they conferred might be more widely dis 

 tributed, and not become the sole property of the inhabitants of one climate. Time 

 the all-wise and beneficent Being has so organised certain classes of animals, and 

 circumstanced them, as to be directed annually, by some pressing want, to seek 

 distant climates, and, after a certain period, to return again to their former quarters ; 

 am 1 that this instinct should be productive of so much good to mankind, anJ, at 

 the same time, be necessary, under its piesent circumstances, for the preservation*** 

 propagation of the species of these several animals.* 



* Partington s &quot; Cyclopaedia.&quot; 



