Essex County herald. [volume] (Guildhall, Vt.) 1873-1964, 1879-03-07

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Upon the leaf Of the cabbage it APP
pears as engraved, in white patches {;
the leaves become deformed and swol-
len or blistered, even before we can
make out fully the cause of the mis-
chief outside. These blistered pus-
tules have minute system of branch
ing threads, which traverse the pulpy
parts of the leaves, and which threads
insinuating themselves between the
cells that constitute the pulp, take
their nutriment at the expense of the
growing foliage.
Its after the pustules assume the
white color and are visible on the skin
or cutiele that the reproductive parts
termed conidia can be detected. See
figure 6. From the mult;tudes of
these beads or spores forming the
white powdefy dust. the term contdia
is applied, which means dlstl:ko
Other plants. besides, are often Affect
ed as the vatercress, pepper grass.
mustard, radish and even the weed
purslane does not escape its ravages.
Its mode of vegetation is one of pecu-
liar interest, in fine one of the most
curious phenomena of plant life, and
indicates in this low order Of vegeta-
ton relation to higher structural
forms. not only in plants but even in
animals. Thus, if q few particles OF
the white dust be immersed in a drop
OF water, and examined under the mi
croscope they will be seen to rapidly
absorb water, and swelling, q large
and obtuse papilla resembling tho
neck of bottle is produced, and a
seeming empty space is formed in tho
contents Of each spore. AS these disap.
pear the whole granular substance be-
comes separated by fine lines into five
to eight portions each, with n small
family eolored, empty space in the
center. These portions are so many
Zoospores. These are soon expelled
one by one, and soon Afterwards be-
gin to move, being provided with
seeming fins or fringes by which they
are enabled to swim about like an an
imalcule: but they are only buds en-
dowed with. motion, same as many
other plants have. These Of course
are capable of injecting plants, as VIC
have seen.
The prodigal provision Of nature is
here, as everywhere, especially in its
lower orders signally manifested, when
we arc told that the immense numbers
of zoospores capable Of being produc-
ed from single infested plant is al,
most beyond calculation. 1t is easy
for million of conidia to be develop
cd from one such plant, each produc-
ing five to eight zoospores. 1t can
scarcely be considered marvellous that
the white rust should be SO common
on plants favorable to its develop
mcnt, the marvel being rather that any
escape.
THE POTATO DISEASE.
Mould is word in common use,
and all will tell you what mould is
yet each will perhaps tell you of dif
ferent kind. This very numerous
family arc called Uyphomycetes, that
is, fungi that grow by throwing out
delicate threads.
OF course their are several distinct
groups.
To the common eye unaided by the
microscope or observation, mildews
mouldiness, and similar microscopic
plants, would be readily confounded
But the mildew is much more highly
developed fungus, and though appar.
emily as dangerous, is not so to the
same extent. The egg mould (Oidi
un) which covers and sutfocatcs the
young gooscberry, or the grape, read
lily yields to agents which will destroy
it, and set free from its threads the
swelling fruit; but the potato mould
for instance. is the inception of the
potato rot, which is so dreaded. The
''monlds" then, as Russell says, "arC
fearful parasitic plants, which riot or
the tender tissues of other plants, ant
eventually cause their DEATH" There
is in this country as many as ter
known fungi infesting the potato. Il
is on this account that those attempt.
ing to describe the potato disease
have differed so widely from eacl
other, while all have brought VI
some facts. The true potato mould
causing so much mischief, is now gen.
orally admitted to be the PeronoSporo
iaJeStans, and were it not for its effects
it would be regarded as q thing o
beauty, Wcro the flies or insects
which are so literally endowed with
eyes, and quite unooncerned about
crops,--to investigate; the leaves OIL
the potato would be quite pretty sci
of objects to examine, presenting white
many branched, and beaded twigged
plants, with egg-shaped seed bodies