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lation, the infestans, should possess a similar faculty. 

 Under all circumstances we can only get to the point 

 that one clique says they exist, while another nega- 

 tives it. This is a very unsatisfactory condition of 

 aifairs for the cultivator of potatoes. M. de Bary says 

 the disease is only carried through winter in the tubers, 

 therefore it is only necessary to destroy all tubers affected 

 by it and the disease becomes extinct, except for the small 

 quantity which is found on other solanaceous plants, 

 which is admitted to be very small. According to M. 

 de Bary's view it would be needless to burn the haulm of 

 diseased potatoes, and it may safely be used to manure 

 land to produce a crop of potatoes in the following 

 year. Mr. Smith says that all haulm in fact, all parts 

 of the diseased plant should be burned. And no one 

 can definitely prove which is right. M. de Bary may 

 be right in saying no resting spores are developed 

 now, but it would be difficult to prove that they were 

 not formed at the time Mr. Smith asserted he detected 

 them. They may not have been formed or present, 

 but having in view the fact that closely allied plants 

 do produce them, it is not outside the bounds of 

 possibility that they may be developed at any future 

 time. Concensus of opinion in one direction induces 

 one to think that M. de Bary's must be the correct 

 view, for the greater number of those who have made 

 investigations follow him; but even majorities have 

 been wrong. Who is to settle the matter? Mean- 

 while, is the farmer to follow the popular verdict, and 

 use his haulm for litter and manure, in which it 



