Microscopical Essays. 6yi 



myftery of nature. On the corona and it's cluflerS depend that 

 property of vegetables, that they can be produced entire from 

 every piece. Thefe cluflers follow the courfe of the other por- 

 tions of the tree ; they are, therefore, every-where ; they are 

 always capable of growing, and their growth, even in a cutting 

 of the fmallefl twig, cannot produce a leaf or any. other part of a 

 vegetable alone, but muff afford the whole, for they are com- 

 plete bodies, and the whole is there waiting only for the oppor- 

 tunities of extenhon. For the knowledge we have of this part 

 we are altogether indebted to Dr. Hill. It remains for future 

 obfervers to confirm or difprove his obfervations. 



Of the Pith. 



The pith is found in the center of every young moot of a tree ; 

 it is large in fome, lefs in others, but prefent in all. It is placed 

 dole within the corona. 



It feems to be nothing more than a congeries of the cellular 

 tiffue ; it is generally found near the center of the tree, incJofed 

 as it were within a tube ; in general, the cells of the pith are 

 larger than thofe of the cellular tiffue, with which, according to 

 Duhamel, it communicates. For the rays which extend from the 

 pith to the bark are, in his opinion, produced from it. Thus, 

 though it may differ in name from the parenchymous parts of the 

 bark, and the radial infertions in the wood, yet it is of the fame 

 nature and texture, and is continuous with them ; fo that, accord- 

 ing to this idea, the Ikin, the parenchyma, the infertions, and the 

 5 pith* 



