NOVEMBER. 13 



In the garden of Moray House, in the Cariongate of the 

 old city, formerly the residence of the Earls of Moray, but 

 occupied in my boyish days (perhaps still) as the Free 

 Church Normal School, there were two (if not more) 

 ancient pear trees, of a fine variety known as the Longue- 

 ville. It is said that the trees were brought from France 

 in the time of Mary of Guise, wife of James V of Scotland, 

 and mother of the famous Mary Queen of Scots that is 

 to say somewhere about the year 1540. At the beginning 

 of this century, therefore, they would be some 260 years 

 old. Even then they were bearing fruit, but sparingly, 

 and apparently they soon ceased to do so, though they 

 remained strong and healthy. Repeated attempts were 

 made to perpetuate the variety by grafting them on to 

 young stocks, and it would seem that the grafts grew and 

 threw out abundance of foliage, but fruit they would not. 

 No doubt this was due to the extreme age of the grafts. 

 It is said that the Longueville pear is still known in the 

 south of Scotland, but I do not remember ever seeing the 

 name in a nurseryman's catalogue. 



Now what is true of trees and their grafts is equally true 

 in almost the same way of such things as potatoes. When 

 we plant the tubers of potatoes we are not dealing with 

 new plants, the product of seeds. Our so-called "seed' 

 potatoes are only short portions of thickened underground 

 stems, and it is quite certain that by continual planting of 

 such tiibers we are perpetuating stocks which may be 

 extremely old perhaps a century or more. This has often 

 seemed to me to be in part the explanation of the sudden 

 outbreak of disease which destroyed the potato crop in 

 Ireland in 1845. The Irish cultivators had to a large 

 extent adopted the lazy-bed system of culture, or want of 

 culture, forking their patches of ground in autumn, taking 

 out all the larger tubers, and leaving in the smaller ones 

 to be the progenitors of the next season's crop. It is 

 impossible to say how long this process had been going on, 

 but it is certain that the stocks must have been very old, 

 and they must also have been impoverished by the treat- 

 ment to which they had been subjected. They were thus 



