New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1875-08-20
~ ,,.nsra,ept and verv acid Guild. Their surfaces


marked by prominent ridges, showing that the car
tilages had been unequally corrodcd by the solution
Moderately sized bits OF the skinned ear of cat, IN
Guiding cartilage areolar and elastic tissue, were
placed on three leaves. Some of the glands were
touched with saliva which caused prompt infection.
Two of the leaves began TO expand after three days.
and the third on the fifth day. The fluid residue left
on their disks consisted in one case of perfectly
TRANSPARENT yscd natter in the other two cases II
contained some elastic tissue andarparently remnants
of half digested areolar tissue. Small smooth bits
of the dried bone of a fowl moistened with saliva
were placed on two leaves. and similarly moistened
splinter of an extremely hard. broed muttoh-cnoP
bone on third leaf The leaves soon became strongly
infected and remained for an unusual length VI
time one leaf for ten and the other two tor nine uas
The hits of bone were surrounded all the time by
acid SECRETION When examined under weak
power they were found quite softened, so that they
were readily penetrated by blunt needle, torn in,o
fbers or compressed. Rather large drops OF MILK
excited so much secretion (which Is very aca 'i''
il sometimes tricked down from the leaves. Minutc
drops of milk placed on leaves, were coaguiated III
about ten minutes. little fresh pollen rom 'ne
common pea was placed on the disks of five leaves,
which soon became closely Infected and renamed
so for two or three days. Examined under the
I
the o-vessels remarkably aggregated. Many had
their contents much shrunl, and some were almost
empty There could be no doubt that the secretion
had penetrated the outer coats of the grains ana had
partially digesed their contents. Droscra IL state
of nature cannot fail 10 profit by this power OF
digestinc pollen, as inumerable grains from the
trees and shrubs which commonly grow Ill the same
neighborhood. would inevitably he caught by the
viscid secretion surrounding many glands.
There are many substances which are not in the
least acted on by the secretion Among these are
bits of human nails balls of hair, the qls OF 1eat
ers pepsn ceulose, gun-cotton fat OIL ana starch
To these may be added dissolved sugar ana gnh'
diluted alcohol, and vegetable infusrons not con
tanning albumen. None of these excite lntecton
1t is remarkable fact, aioTdng important evidence
that the ferment of droera closely resembles II IL be
not identical with pepaip that none OF these same
substances as far il is known are digesed by 'De
gastric Juice of animals although some OF them are
acted On by the other secretions OF The alimehiiF
canal.
similar taste for animal food, accompanied with
the power of digestion and assimilation, is found IN
other plants of the drosera family, especially III the
dionaa orVenuss fy-trap as il is called. This plant
is native of North Carolina, where 1t grows Ill
moist situations and has long since attracted the
attention of American bOianists. The leaves nave
two lobes standing nj rather less than rght angie
to each other. Three minute pointed hlanents,
placed triangulaTy, project from the upper surface
Of each lobe. They remarkable for an extreme
sensitiyepess 70 a touch as is shown not by their
own movements, bat by that of the lJbes. The mar
gins of the leaf prolonged into sharp, red pro-
iections, like spikes into each OF which enters
bundle of spiral vessels The upper surface OF the
leaf is tckly covered, except towards the margins
i 1, .l.al, p.lar
the rest of the leaf being green. There no glands
on the spikes on the footstalks. The glands are
formed of from twenty 10 thirty polygondl cells,
filed wthpurple fluid. Then uppersurface il convex
They stand on very short redicels into which spiral
vessels do not enter differing i'll this respect from
the tentacles of droseIa. They secrete only when
excited by the absorption of certain matters. The
sensitive flaments are formed of several rows OF
elongated cells, filed with purplish fluid. From
their tips their bases they are eXquisiiely sesl-
tive to a momcntary touch. They can scarcely be
touched with any hard object however lightly or
quickly, without causing the lobes TO close. piece
of very delicate human hair, held dangling over
filament and swayed to and fro tilament, did
not excite any movement. But when q thick cotton
thread of the same length was similarly swayed, the
obes closed. Pinches of fine wheaton flour. dropped
from hight, produced no effect. The abOve-men-
!
with projection of one inch, this length being suli
GENTLY rigid 10 support itself in nearly horizontal
line The extremity was then brought into contact
| with the top of a flament and the lobe instantly
closed On another occasion two or three touches
of the same kind were necessary before any move
ment ensued. But, although these fiianents are so
sensitive to a mOmentary and delicate touch they
are far less sensitive than the glands of
the drosc1a to prolonged pressure. This
singular difference evidently stands in rela-
ton TO the habits Of the two plants. If a
minute insect with its delicate feet aGghts on the
glands of droscra il is caught by the viscid secre
tion. and the slight, though prolonged pressure,
gives notice Of the presence OF prey which Ii secured
by the slow bending of the tentacles. On the other
hand. tine sensitive flaments of dionRa are not
vscd and the capture of insects is only assured by
their senstiveness to a momentary touch, followed
by the rapid closing of the lobes. The glands on the
upper surface of the lobes have the power both Of
secretion and absorption but unlike those of drosera
they do not secroe until excited by the absorption
of nitrocenous matter. No other matter produces
this effect Articles such as bits of wood cork,
moss paper stone or glass may be left for length
of time on the surface of a leaf, and il will remain
ouite dy But if the lobes are made TO close over
bit of meat OF an insect the result is different, for
the Glands over the whole surface OF the leaf will
now secrete copiously. The secretion is almost
colorless slightly mucilagnous. and more strongly
acid than that of drosera. 1t is 30 cOpious that
when Oh one occasion, leaf was cut open, on which
small piece of albumen had been placed 10 hours
before. drops rolled off the leaf On another occa-
sion. in which leaf with an incloscd bit Of roast
meat spontaneously opened after eight days, there
was sonuch secretion that il tricklcd down.
There is great difference between drosera and
dionpa in the effects produced by mechanical Trita
ton on the one hand, and the absorption Of animal
matter on the other. Particles of glass placed on
the glands of dtoSera excite movement within