LETTER IX. 



85 



flowers, and fruit, goes far to make good our assertion, 

 that the parts in question then die, and never Hve 

 again ? 



12. If we pursue this matter a little further, we 

 shall not only see still more clearly, I think, the reason 

 of this difference in the constitution of plants and ani- 

 mals, but be able to trace a closer affinity between the 

 tree and the annual in relation to the duration of their 

 vitality — nay, an actual identity between them in this 

 respect. 



13. The objects for which animals exist, and for 

 which they have been created, may, in a general way, 

 be said to have reference to the mental powers bestowed 

 upon them. Those objects require the maintenance 

 of the animal structures, in a state of vitality and effi- 

 ciency, for a certain time, which is very various in 

 different structures and in different kinds of animals. 

 Agreeably to the laws of vitaHty, this can be accom- 

 plished only by an incessant change and renewal of 

 substance ; and accordingly this change forms a dis- 

 tinguishing characteristic of the vital actions of animals. 

 To this it may be added, that their several structures 

 are designed either to serve as the seat or the instru- 

 ments of the mental principle within them, or to 

 provide for the continued maintenance of the entire 

 organism. 



14. On the other hand, the objects for which vege- 

 tables exist have reference to animals. Vegetables 



