The Florida agriculturist., 1884-09-10
How Our Carp Are Destroyed

" N~A ~~A RAO OCoOkOJOu'1
There is little plant, common enough
in our ponds, and known as bladder
wort, which has suddenly sprung int
Importance for breeders OF carp. TIL,
badder~woT4n (genas TtrScularid) is
rootless plant fond OF still water anC
usually found floating hall In and hal
hah ont 'of watet, the branching an,
SteFh-like leaves forming submerged itoa
from which rises The Hover stem. n,
the leav3ss are attached 8'Ai;ie9sSV insect
like hladaefs illeA with W;stess &lR8 vary
ing ihssiae i'm itlle tliffetiRt Sseeiess seaeA
}tlg ttt tlnttss q tlitlHiestr' 'f '}iSt6BR 9A an
inth
1T W,es Qfaallv. ahR v.ah 8seA
probability Niib30Sliik taat eAeSe hltNf
{lalss served tflte RiiiigpSas QS HQasSs 6oS
jliitil y tfl4w WEARS asSs0 u NsS taken e9E
gtalhaH telib aiir a}e6 ao6 water Rlled
phenl lTt lfS 9i}AN kfs,2s, hQweYeR that
tlhte 4isaeasrs seeSe 4 a2ssae esSefke ptsFpose
slialh saeeelcf a. Keep the head OF the plant
above Wseers theN are the digestive
organs oS the otarteol0rsse, an8 at the
SSsNe tiSse are ~ colsStvtste6 as 10 form
a very Ingenious but extremely simple
trap tor catching food Il Is into these
AlatSierS that thousands OF carp eggs
ind their Unwitting Way, together with
objects, both animate and inanimate.
Il is only recently that the Itricaldria
has been accused Of destroying carp eggs,
but for nearly thirty years it has been
known as q receiver of small insects and
crustaceans, and it has been known as IN
insect feeder for at least twenty years.
Mrs. Treat, OF this country, i'll 1875 gave
full and interesting description of the
habits OF one specieS( JtricUldrid cldndes-
tind), and Darwin and others, OF Europe,
studied the habits of other species in
Europe, and elsewhere.
In its character as an insectivorous
plant the bladder-wort might fail to-
arouse general interest, but as a des-
troyer of carp it has commercial as well
as botanical and scientific character
The common bladder-wort (Jtrjcuidrid
rplgdrjs) affords the easiest subject for
study inasmuch as its bladders reach
the largest size and may be satisfactorily
examined with moderate magniter, |
The bladder is pear-shaped, with an
opening at the small end. Around the
mouth are antennm-like projections or
bristles, which, according to Darwin, !
are for the purpose OF warding off and !
Keeping out insects q too great size. |
The mouth is closed by valve which |
Yields readily to light pressure, but offers |,
an immovable barrier to the once captur- |
ed creature The utmost strength compa-
tible with sucha structure has apparently !
been attained The valve is thin and (
transparent plate, and by means of the |
water behind it, is made to stand out a
bright spot, which Darwin thinks may
attracts the tiny denizens OF the water,
for they swim up to the mouth and crawl
into the bladder by the readily yielding
door. AS there is no seductive secretion
here, as in the case of many insect des-
troying plants, the great naturalist $
surmise is probably correct.
Some of the insectivorous plants, on
catching their prey, at once pour out a
digestive fluid analogous to the gastric
Juice of the human stomach, but with
the UtriculdriU it is not so. The insect
or other food when caught in the bladder
are merely captives, and swim about i'll
their confined quarters with eager activi-
ty in their endeavor to find an outlet,
until asphyXia for lack of oxygen comes
on. Even now the plant makes no effort
to digest the animal food, but waits pa
tiently until decay takes place, and the
animal matter is 10y putrefaction resolved
into fluids which the numerous papil@
lining the bladder can absorb. u
Darwin sexperiments showednot only
that living, animals could make their
way into the bladder, but that ;naninate
objects falling ON the valve would be en-
quilted with lightning-like rapidity.
With all this information TO begin with,
it is not strange that naturalists should
turn to the bladder-wort to seek solu
ton for the great destruction OF the carp,
for the carnivorous plant was known to
possess facilities not only for the capture
of floating spawn, but even OF the newly
hatched fish. Examination and repeated
experiment proved conclusively that the
greedy little bladders were making sad
havoc with the fish, and III consequence
carp breeders are hidden to open wal
vigorously on Utricularia and all its spe
cies. 1t may seem at a hasty glance
that the small bladders can hardly be
responsible for any very extensive de
struction of eggs or small fish, but thu
doubters of the ability of insignifican
agents, acting together, to produce stu
pendous effects may be referred to TIN
microscopic trizopods or the earth worm
each in their own way performing won
deriul feats in the way OF earth building
and earth preserving. .-Sctcntfc dbtrrs
can.
"''" The Grass Tree. ~
Down in Australia, that great islam