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jointly, from the leaves vegetating in an ungenial 

 atmosphere, or from their heing too reduced in num- 

 ber. In either case, we consider with Dr. Lindley, 

 that a deficiency of organizable matter is the conse- 

 quence ; and such deficiency is a satisfactory explana- 

 tion why the disease occurs. It must never be for- 

 gotten (says the authority just quoted) that plants, 

 like animals, consist of two essentially distinct parts ; 

 the one the organised material of their structure, the 

 other the organizable matter out of which additions 

 are to be made to that structure ; and that under no 

 circumstances whatsoever can growth take place, ex- 

 cept in the presence of the latter. This law is not 

 only one of the foundations of vegetable physiology, 

 but one of the most important of all facts for the 

 gardener to bear in mind, explaining as it does the 

 sources of success or failure in multitudes of the 

 operations in which he is engaged. {Gardener 's 

 Chronicle, 1843, 709.) 



Shrivelling, or rather the withering of grapes pro- 

 duced from weakness, is a very different disease from 

 shanking. Shanking takes place almost as quickly 

 as a tree withers when struck by lightning, but shri- 

 velling is much more gradual in its advance, and oc- 

 curs, at first, without any disease appearing in the 

 footstalks of the berries. The other symptoms are, 

 that after the berries are formed they advance pretty 

 rapidly in size until the period when the seeds are 



