Vermont watchman and State journal. [volume] (Montpelier, Vt.) 1836-1883, 1847-03-04
THE MICROSCOPE AND ITS
REVELATIONS.
From tho Westminster Review.
INFUsoRIA-THE PoLYGAsTRIA.

INFUsoRIA-THE PoLYGAsTRIA
We turn now to the consideration of the
wondrous revelations of this instrument
and we will first speak of that vast world of
animal life with which, but for its aid, we
should be wholly unacquainted 1t would
be utterly impossible for us, within the linn
its to which we are confined, to give de-
tailed account of all the anmalcules which,
under the name of Infusoria have been ex-
AHMED, described and figured by the nat
uralists who have devoted themselves to this
branch of study Our endeavours in the
present article must necessarily be confined
to the attempt to present to the general rea-
der view of the extraordinary edifice rear
ed by means of the microscope in the field
of physical science, and to show how the eve
of man is here opened to penetrate the most
profound, and formerly unsupported, secrets
of nature.
The vast numbers of animalcues with
which the microscope has made us acquain-
ted, were first detected in water in which
vegetable matters, such as hay, grass, &c,
had been allowed to maccrate and as they
were almost invariably found in such infiI-
sions, it was considered by early investiga-
tors that they were peculiar to them hence
the general term lNFUsoRIA was given to
them; and although it is now known that
these vegetable infusions have no relation to
the origin of such creatures, except in so far
as they provide proper medium for the de-
velopment of their ova, everywhere presents
yet, for the sake of convenience, the gener-
al term Infusoria' is still retained by nat
uralists. Perhaps the best general idea of
the appearance of some of the animalcules
to an observer, for the first time, will be Civ
en- by the following extract from DR.. Man
tells work -
From some water containing aquatic
plants, collected from pond on Chaplain
Common, | select a small twig, to which are
attached few delicate flakes, apparently of
slime or jelly some minute fbres standing
erect here and there on the twig are also
dimly visible to the naked eye This twig,
with drop or two of water, we will put be-
tween two thin plates of glass, and place I'M
der the field of view of a microscope, having
lenses that magnify the image of an object
two hundred times in linear dimensions. Up
on looking through the instrument we find
the fluid swarming with animals of various
shapes and magnitudes. Some are darling
through the water with great rapidity, while
others are pursuing and devouring creatures
more infintesimal than themselves. Many
are attached to the twig by long delicate
threads 1.-THE Vorticellp) several have their
bodies inclosed in transparent tube, from
one end ofwhich the animal partly protrudes,
and then recedes (the Floscularie); while
numbers are covered by an elegant shell or
II ba l. lie
(the Monads), many of WHICH are so small
that millions might be contained in Il single
drop of water, appear like mere animated
globules, free, single, aud ofvarious colours,
sporting about in every direction. Numer-
Gus species resemble pearly or opaline cups
or vases, fringed round the margin with del
icate fibres that are in constant oscillation
(the Vortcelle). Some of these are attach
ed by spiral tendrlls; others are united by a
slender stem to one common trunk, appear
ing like bunch of harebells (the Carchesi-
um) others are of a globular form, and
grouped together in definite pattern on a
tabular or spherical membraneous case for a
certain period of their existence, and ulti-
mately become detached and locomotive (the
Gonum and Volvox); while many are per-
manently clustered together, and die if sep
arated from the parent mass. No organs of
progressive motion, similar to those of beasts,
birds, or fishes, are observable in these be-
ings; yet they traverse the water with ra-
pidity, without the aid of limbs or fins, and
though many species are destitute of eyes,
yet all possess an accurate perception of the
presence of other bodies, and pursue and
capture their prey with unerring purpose"
- Thoughts on Animalcules,' PIP. 9, 10.
Much as has been done in this department
of science, our knowledge of the infusory
beings is still limited but there is every rea-
son to believe that they do not take their sta
ton among the links Of the animal chain ac-
cording to their dimensions, but from their
structure. The simplest and smallest is as
much an animal as the prouder examples OF
natures works; and it is equally the object
of the Creators care and contrivancc. To
| Ehrenberg are we indebted for classical
ton of the Infusoria, which has been follow
ed and adopted by all subsequent philoso-
! pliers. He divides them into two classes
First, The PoLYGAsTRIA and, secondly,
The RoTAToRIA
The Polygastrla, or Polygastrica, are, as
the name would imply, natural group OF
dlllllldlS CHdI dCleTlLcu Dy tHe digestive VI SdL
being composed of several little gobular
bladders connected to each other by COM
mon tube and these globular tubes receive
and digest the matter on which the animal
cule feeds when in sufficiently commnuted
or divided state. That this is their real or.
| ganization we have evident proof; for, by an
ingenious process, first adopted, we believe,
/ by Gleichen Won Russivarm, these little cav
tiles occurring in the bodies of the poygas-
tria can be more infinitely examined The
process to which we allude was that of col
curing the water in which the animalcules
were contained by carmine or indigo. The
tlnged water was thus traced from cav
ty to cavity until its final election from
the last of the series The Polygastria pre-
sent great diversity both of figure and di-
mansions. None of them exceed the twelfth
of an inch in length, and some of the small
Ter species, even when full grown, are but
the two-thousandth part of that measure
indeed, so minute must be many ofthe young
of these lnfusoria, that they cannot be re-
cognized by our microscopes Again, 9TH
ers individually so small as to be almost in
visible, form, when aggregated, green, red,
yellow blue, brown and black coloured mas