MOULDS. 145 



come general in the South of England, and the 

 next week there were but few sound samples of 

 potatoes in the London market. Early in Septem- 

 ber the disease had commenced its ravages in 

 Ireland, and shortly afterwards it was discovered in 

 Scotland. With the same rapidity it seems to have 

 spread throughout Europe and North America, or 

 at least the western portion of the former and the 

 northern districts of the latter. It must not be 

 imagined, however, that the Isle of Wight was the 

 centre from which this disease spread over such an 

 extended area and with such alarming rapidity. 

 From this spot it doubtless made its first appear- 

 ance that year amongst our own crops, but there 

 is not the least doubt of its existence both on the 

 continent of Europe and in North America in the 

 previous year, and the farmers of Belgium had 

 noted its appearance in the province of Liege as 

 far back as 1842 and 1843. Other diseases had 

 been observed affecting the potato crop before, and 

 one which was also associated with a parasitic 

 fungus had made its appearance in 1815. It is 

 also exceedingly probable that, in a milder form, 

 the murrain was present with, us a year or two 

 before it broke out to such an alarming extent. 

 A correspondent to the Gardeners' Chronicle, in 

 1844, notices it in the Isle of Thanet, and another 

 testifies to its occurrence in districts of Ireland for 

 two or three years previous to its general outbreak. 

 The description of the disease in Canada, in 1844, 



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