OF NATURAL HISTORY. 



43 



The life of animals is diverfified by a number of fuccefllve chan- 

 ges. Infancy, youth, manhood, old age, are charadteriled by imbe- 

 cillity, beauty, fertility, dotage. All thefe vIcifTitudes are confpicu- 

 ous in the vegetable world. Weak and tender in infancy, beautiful 

 and vigorous in youth, robuft and fruitful in manhood, and, when 

 old age approaches, the head droops, the fprings of life dry up, and 

 the tottering vegetable, like the animal, returns to that duft from 

 which it fprung. 



Upon the whole, by taking a retrofpedive view of the extreme 

 difficulty of afcertaining the boundaries which diftinguifli the animal 

 from the vegetable, and of the fimilarities in their ftrudure and or- 

 gans, in their growth and nourifhment, in their diflemination and 

 decay, it is apparent, that both thefe kingdoms conftitute the fame 

 order of beings, and that Nature, in the formation of them, has ope- 

 rated upon one great and common model. 



F 2 ■ CHAP. 



