368 
On the Potato Disease. 
so ; for apples are said to be natives of Syria, and are alluded to m 
Scripture ; although many of our oldest sorts bear French names, 
and no doubt were brought to us from Normandy. Apricots, and 
many other trees from warmer climates, are very liable to its 
attack, some varieties more so than others ; thus, last spring, I 
had one or two branches of Moor-park apricot, which I had 
budded three years before on the common sort, destroyed, while 
the parent plant was uninjured, being, doubtless, rnore hardy. If 
a blotcli of canker on a fruit-tree is examined soon after its ap- 
pearance (which is often very sudden when hot days in spring are 
immediately succeeded by sharp frosts or cutting easterly winds), 
it will be found that the brown or ferruginous fluid corrodes the 
inner coats of the bark in an uneven manner, just as it does on 
the potato — usually forming a band or ring round the shoot. This, 
however, frequently throws out granulous matter, as an effort to 
counteract its progress, which is sometimes successful for a season ; 
at other times, and much oftener, the canker is victorious, follow- 
ing the course of the medullary rays into the pith; the contest is 
then at an end, and the upper part of the shoot dies. It often 
happens also that two or three isolated blotches arise on the same 
shoot; hundreds of instances of which I met with on the stalks, as 
well as on the potatoes themselves, last year: in fact, it is charac- 
teristic of the disease to appear in that form. The potato-stalks, 
however, being more herbaceous, and constructed to endure only 
for a single season, become a quicker and more easy prey to its 
mortiferous foe. Tlie same effects are likewise frequently produced 
on the leaves and stalks of many other tender and half-hardy 
plants when exposed to sudden and violent changes of tempera- 
ture. Cauliflowers, if badly wintered, and cucumbers* and melon- 
plants, are more or less subject to this disease, and are soon utterly 
destroyed by it. Gardeners usually term it " damping," or 
shanking off." Immense quantities of cucumber-plants were de- 
stroyed last season as stated in tlie 'Gardener's Chronicle' — some 
I witnessed myself; and if in circumstances favourable to its de- 
velopment, mildew, in one or other of its varied forms, succeeds. 
Several other plantsf were aflfected in a similar manner ; and the 
same disease has this year caused sad havoc amongst tulips, which 
looked very healthy during the early part of the year, but were 
struck by the cold and wet weather which ensued afterwards ; 
many of tlie blotches on the leaves being also covered with mil- 
dew, as in fig. 1, D. 
* The following answer was given. May 23, to a person who complained 
of his cucumbers being diseased, by the editor of the ' Gardener's Chro- 
nicle :' — " It is impossible to say what these cucumbers ail. They are 
cankered : one would have thought that they were overwatered in too low 
a temperature," &c. 
i' Carrots, onions, tomatoes, mangold wurzel, &c., of my own growth. 
