102 



as the zoophyte, or even as the polypus and the ^ 

 hirudo — annuals that may be cut into pieces, and 

 each section become a perfect individual ; animals 

 whose heads may be taken off and grafted upon other 

 bodies ; animals that may be turned with their out- 

 sides inwards, and yet without any apparent incon- 

 venience. If plants be endowed with sensation of 

 the most limited degree, it explains the cause, throws 

 light upon the prevention of many diseases that affect 

 those which are the object of cultivation ; warns the 

 tiller of the soil from the late performance of many 

 of his operations, and teaches him generally to be 

 less violent in his field practice. If a g;rape vine be 

 pruned too late in the spring, the bleeding or effusion 

 of sap has been known to be so violent, that the 

 tree has died from absolute exhaustion. Stone fruits, 

 if severely wounded, are frequently destroyed by the 

 inroads of a disease resembling in all its characteristics 

 the cancerous affections of animals ; and we have 

 known a whole crop of wheat affected with a swelling 

 of the stem or culm, evidently caused by an extrava- 

 sation of the sap from its ruptured internal vessels, 

 owing to the roller being passed over the crop when 

 of a growth somewhat too forward. 



After these prefatory remarks, intended to save from 

 fundamental objection the opinion we entertain, that 

 most, if not all the diseases of plants, are connected 



