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old tubers of the Potatos, were entirely gone, but the Potatos 

 whether large or small, were quite sound. Again, the old 

 sets were not always rotten. Further, the disease does not 

 seem to have any uniform time of development either as re- 

 gards season of the year or state of plant. Potato plants in 

 all stages of growth seem to have been attacked; hence sound 

 tubers were found ranging in size from marbles to full-size 

 Potatos, and the latter seem little if at all deteriorated in 

 quality by the loss of the tops. In all these particulars the 

 new disease seems identical in its effects with the old"curl," 

 and no doubt tubers without tops, and roots of small tubers 

 undeveloped or arrested by some cause, have been more 

 or less common from the beginning of the cultivation of 

 the Potato in Europe. The fact is quite familiar to all who 

 have had experience in the lifting of Potatos, consequently 

 I think we have little to fear from the new disease, except- 

 ing in so far as it may strengthen and multiply our old 

 foe, the Peronospora infestans. 



Mr. Smith's discoveries concerning the resting-spores 

 of the latter would point to steeps for the seed, and frequent 

 changes of ground for the crop, as the likeliest means of 

 killing or starving out the disease. If it is possible to use 

 steeps that will kill those resting-spores in or upon the 

 Potatos without injuring the vitality of the seeds, we may 

 thus rid ourselves of the pest. Again, if, as seems proba- 

 ble, the spores cannot rest more than a season, may it not 

 be possible to starve out the Peronospora by growing such 

 crops in succession to Potatos as the spores can neither 

 vegetate nor develope into other forms upon ? A further 

 knowledge of the likes and dislikes of the Peronospora in 

 all its multiform modes or forms of life might enable us to 

 select anti-Peronospora crops to starve or poison out the 

 pest in all its stages. Unfortunately the cottager is almost 

 always obliged, from the smallness of his holding, to grow 

 Potatos after Potatos on some portion of his garden. This 

 is doubtless a sure mode of perpetuating the Potato disease ; 



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