42 



THE PHILOSOPHY 



ftrudtions, tumors, and a gradual refolution and corruption of the 

 whole fabrick. Many of the difeafes of plants are produced by the 

 infe£t tribes. . Their wounds and depredations are not confined to 

 particular parts, but extend from the root to the ftem, branches, 

 leaves, flowers, and fruit. Infeds not only injure the fubftance of 

 plants, but, by feeding on their juices, deprive them of a part of 

 their nourifliment, and occafion various difeafes or changes in their 

 organization. Other difeafes of plants derive their origin from change 

 of climate, from miafmata or noxious vapours in the atmofphere, 

 and from improper culture. When wounded by external inju- 

 ries, vegetables difcharge their blood in copious dreams. If the 

 wound be not mortal, the fibres on all fides gradually flioot out, and 

 clofe the fradture by a callous fubftance. 



From this general enumeration, it is obvious, that the difeafes of 

 plants are not only fimilar to thofe of animals, but proceed from the 

 fame caufes. In both kingdoms, fome difeafes are only partial or 

 fuperficial, and are cured either by Nature, or by the afliftance of 

 art. Others are mortal, and fucceeded by a total putrefaction or de- 

 compofition of thq individual. 



But, though plants fhould efcape the numberlefs difeafes which 

 daily threaten them, they have no defence againft the flower ap- 

 proaches of old age, and its unavoidable confequence, death. In 

 progrefs of time, the veflels gradually harden and lofe their tone. 

 The juices no longer move with equal celerity as in youth. They 

 are not abforbed with the fame precifion. They at laft ftagnate and 

 corrupt. This corruption is foon communicated to the vefl'els in 

 which the juices are contained, and produces a total cefTation of all 

 the vital fundions. 



The 



