On the Potato Disease. 
350 
great number of these shrivelled cords still adhered to the po- 
tatoes. 
The discoloration had not descended more than 1 -8th of an 
inch under the cuticle, but a much greater quantity of the large 
potatoes was affected than of the small ones. 
Two pieces of Jersey blue at this time, September 3, began to 
assume the same morbid appearance as the others ; the tops, it 
is tme, were green, but it was not of a healthy hue, and on a close 
inspection the awful spot was perceptible both on the leaves and 
stalks : most of the lower leaves and petioles were diseased ; many 
had even fallen from their axils. I marked several plaafs, and 
picked off every spotted leaf, but in two days there were as many 
more, althougli the tops still continued of a sickly green colour, 
even after the blotches had encircled the stems. 
Tlie weather about this time was very hot and dry. These 
potatoes were taken up on the 22nd of September, nearly a month 
sooner tlian usual, and of these also the large ones were much 
more diseased than the small ones. A neighbour also, whom I 
supplied with sets of this variety, lost all except some of the small 
ones. The potatoes, however, did not generally grow so large 
last year as in ordinary seasons. I also observed at the time of 
taking up that a great number of the more slender plants which 
were quite dead, and appeared therefore to have yielded to the 
first attack (as the tubers all parted from the roots), had not a 
single unsound potato under them, while the strongest plants, of 
which the haulm at top continued green to the last, had in many 
cases not a sound one attached to them. My loss was heaviest 
on the blue, and, including those picked out since they were taken 
up, amounted to one-sixth of the crop. 
The above is a brief description of the appearance both of early 
and late sorts ; the former being constitutionally the most tender, 
the latter the most robust. 
I have examined many other crops in several counties of Eng- 
land, but found them differ only in degree : of some upwards of 
9-lOths being destroyed, of others scarcely any. 
It has been generally considered that the disease was quite new 
to this country. I am, however, inclined to think otherwise, if 
only from the following circumstances which have come under 
my own observation : — 
In 1841 I purchased one ton of York red potatoes in London, 
for planting, and while they were being cut I noticed exactly the 
same kind of blotches upon them running about i of an inch under 
the skin, and containing the same dark shiny kind of fluid; and 
although these parts were cut out, more than half of the sets never 
came up, and the shoots of those that did were not thicker than 
straws, and many of these rotted off in blotches afterwards. (Just 
