The Sun.
London, England, 1847-06-23 00:00:00

Or MAIN LINE.)

The case for the Leeds and Thirsk Company haviag
been closed, the Committee were engaged the whole of
the day in receiving evidence in favour of this Bill.

STANDING ORDERS COIVIMITTEE.
HOUSE OF LORDS.
The following Bills went through Committee :
London and North Western Railway, Birmingham and
Lichfield Line, Blackburn, Darwen, and Bolton Rail-
way Amendment.
Aberdeen Railway (Brechin Branch).
The following Bills were adjourned until to-morrow:—
Shrewsbury and Chester Railway.
South Yorkshire, Doncaster and Goole Railway.
Liverpool, Manchester and Newcastle-upon-Tyne Rail-
way (Alteration of Main Line).
Chester and Holyhead Railway.
Reading, Guildford, and Reigate Railway.

RE-APPEARANCE OF THE
POTATO DISEASE.
TO THE EDITOR OP THE TIMES.

Sir,—As your journal has contain-eds number of
articles upon the potato disease, in which it has
been attributed to the attacks of aphides, I beg
to request the insertion in your paper of the
following observations relative to its re-appear-
ance, at a moment when the generally healthy
appearance of the crops and the singular absence of
aphides might induce a false security and lead to irre-
mediable evils ; and which are an abstract of a paper
read by me at the Linnean Society on Tuesday, the 15th
inst.; my object being to disprove the assertion which
has been circulated by Mr. Alfred Smee, with so much
activity, that the disease has been entirely produced by
the attacks of a species of aphis.
The arguments I adduce in opposition to this theory
are— _ _ _

1. That the aphis which has been found upon the
potato, and thence considered as the cause of the disease,
is neither a newly created nor a newly imported species,
but was well known long before the disease in question
appeared.
2. That the disease itself has not been known until
the last few years.
3. That the disease may occur independent of aphides.
4. That aphides may abound on a plant without pro-
ducing the real disease.
5. That the results produced by the attacks of aphides
upon a plant are of a widely different character from
those exhibited by the plants attacked by this disease.
6. That the disease in question may appear in the off-
spring of a sound parent tuber ; and
7. That the disease appears in many respects to be
analogous to the cholera, and may thence, for the sake
of distinction, be termed the potato cholera.
The facts already before the public fully confirm these
arguments, which are corroborated by other circum-
stances which I have noticed within the last few days in
my own kitchen garden in Hammersmith, and which are
briefly as follow:—
On the 4th inst., a few plants were observed sickly in
appearance, with the leaves drooping and yellow in
colour ; the remainder of the crop having a remarkably
healthy appearance and being singularly free from
insects of all kinds. _ _

On taking up these drooping specimens, the haulm or
stem for about two inches below the surface of the
ground was found to be dried and shriveled up in ap-
pearance, and of a dirty brown colour; whilst the tuber
from which it had sprung, and which had been set entire
last autumn, was still found perfectly sound, thus
proving the absence of disease inherited from the parent
plant. With the exception of these few plants the
entire crop retained its healthy appearance until
Sunday afternoon, the 13th instant, when a great
number of the plants in two of the beds were observed
flagging, just as though they had been trampled over by
dogs, which has since been followed by the same appear-
ance in other parts of the garden. It is proper here to
state that no attempts had been previously made to rid
the plants of insects, nor had the ground received other
than the ordinary treatment ; the last year's crop in
my garden having been singularly free from disease.
On examining some of these plants on the following
morning the haulm below the surface of the ground
was found to present the same dried, withered, and dis-
coloured appearance as in the specimens examined ten
days previously; the fibres of the roots being likewise
dry and incapable of performing their proper functions,
and which would produce discoloured blotches on the
leaves in a subsequent stage of the disease. The plants
at the same time were free from insects, and the parent
tuber remained in several of them, to all appearance, as
sound as when first planted. A number of the plants
thus attacked were exhibited to the meeting.
This sudden drooping of so many of the plants, which
up to that time had appeared so healthy, led to the
examination of some of those which still remained erect,
when it was found that even some of these presented
precisely the same appearance as those which had
dropped, and which would doubtless in a few days have
shared the same fate as the others. Nothing, there-
fore, can be more fallacious than to depend upon
the present general healthy appearance of the crop
throughout the country or its freedom from aphides.
The theory of Mr. Alfred Smee is, as that gentleman is
well aware, rejected by every zoologist and botanist of
distinctionin London, and its reiteration at the present
critical moment is a gross attempt to mislead the public,
and may be productive of the greatest evil by inducing
security (owing to the absence of aphides), until too late
in the season to remedy the eviL—l am, sir, your very
obedient servant,
JOHN 0. WESTWOOD,
Secretary of the Entomological Society.
St. Peter's, Hammersmith, June 16.