162 On the Prevention of Curl and Dry-Eat in Potatoes. 
drawn to the failures in the potato-crop which had caused so 
much discussion in Scotland and elsewhere, I paid more than 
ordinary attention to the selection of seed in this instance, and 
made choice of two kinds of round red potatoes, both of which 
were quite new to my land. One of them had been procured 
from Messrs. Drummond, Stirling, in 1835 ; the other from 
Messrs. Lawson, Edinburgh, in 1837; and the gentleman who 
had grown them in the intervening seasons, having two farms, one 
of stiff, the other of light land, had changed his sets regularly from 
one to the other. He spoke highly of both kinds, and when 
boiled they were mealy and good : one kind, however, more so 
than the other. The land on which I planted them, a sandy loam 
lying near the rock (geological formation — new red sandstone), was 
in a high state of cultivation, having had a heavy crop of swedes 
consumed on the land by sheep, the property of the off-going 
tenant ; and my reason for planting it with potatoes was solely 
because I was aware that if sown with corn it would be so lodged 
as to be nearly worthless. I naturally anticipated a heavy crop. 
They were planted in the last week in April, the season remark- 
ably favourable ; and I was much disappointed to find that the 
braird was weakly, and soon showed symptoms of curl. This in- 
creased, and though few of the plants perished, nearly the whole 
were unhealthy. 1 particularly noticed that the kind of potato 
which had been the most mealy when boiled suffered most from 
the curl ; and though, from the great richness of the land, they 
grew, and gave a produce greater than could have been expected 
under the circumstances, it was decidedly a failing crop. 1 was 
so much surprised at the appearance of curl that 1 watched and 
examined the plants at several periods of their growth, taking up 
roots here and there wherever I observed one either better or worse 
than its neighbours. The appearance of all those affected was 
nearly the same. The set, as long as the weather was dry, 
crumbled and perished — the disease seeming to proceed from 
certain spots or pits as centres, and gradually destroying the 
whole set. The cut sets were the worst, and the decay always 
commenced from the cut side of the set, but the whole oneSsalso 
suffered. As soon as the weather became wet, these appearances 
changed, and the diseased portion of the set resembled a brown 
sjjonge, which after a short time became black and offensive. 
The effect on the plant was well marked. Wherever the disease 
had made a decided impression on the set, the stalks of the plant 
were marked with brown streaks and patches, and evidently 
showed that the juices which they were conducting from the set 
were vitiated and noxious. The part of the stalk to which 1 
directed my attention was that underground, in which it was easy 
to trace the progress of the disease, from tiieir being white and 
