PRESERVING SPIDERS, GALLY-WORMS, AND INSECTS.
SPIDERS.
The general directions which we shall give respecting Insects, hold
good as to Spiders, only we must mention there is considerable
difficulty in preserving the bodies of Spiders, which generally, in a
very short time, shrink into a shapeless mass. To prevent this, the
body should be pricked with the triangular awl and the contents pressed
out; it should then be stuffed with very fine carded cotton or down,
which can be pushed in by a pricker, blunted a little at the point.
When properly distended, the small aperture should be filled up with
a little cement, or a solution of gum-arabic. The legs of the larger
species, such as the Bird-catching Mygale and the Scorpions, are also
liable to shrink, and should be stuffed in the same manner as that of
the body.
In those species of Spiders which we have thus prepared, and whose
colors are rich and likely to be affected by the action of the
atmosphere, we must endeavor to arrest its progress by immediately
imbuing the animal, after it is set up, with the solution of corrosive
sublimate, and in an hour after with a thin coating of a very weak
white-spirit varnish; for this purpose, take a tea-spoonful of
the ordinary white-spirit or elastic varnish, and add to it two
tea-spoonfuls of spirit of wine; apply this wash with a fine camel-hair
brush, which will quickly dry, and have a strong tendency to preserve
the color. The varnish, being thus reduced in strength, will not leave
any gloss on the insect, nor will it be at all perceptible.
Mr. Samouelle, author of "The Entomologist's Useful Compendium," in
speaking of preserving Spiders, says: "The best preserved specimens
that I have seen are those where the contents of the abdomen have been
taken out and filled with fine sand. I have preserved several in this
way, and find it answers the purpose."
Mr. Donovan makes the following observations on the preservation of
Spiders:
"To determine whether some species of Spiders could be preserved with
their natural colors, I put several into spirits of wine; those with
gibbous bodies soon after discharged a very considerable quantity of
viscid matter, and therewith all their beautiful colors; the smallest
retained their form, and only appeared rather paler in the other colors
than when they were living.
"During the course of last Summer, among other Spiders, I met with a
rare species; it was of a bright yellow color, elegantly marked with
black, red, green, and purple; by some accident it was unfortunately
crushed to pieces in the chip-box wherein it was confined, and was,
therefore, thrown aside as useless; a month or more after that time I
observed that such parts of the skin as had dried against the inside
of the box retained the original brightness of color in a considerable
degree. To further the experiment, I made a similar attempt, with some
caution, on the body of another Spider, and, though the colors were not
perfectly preserved, they appeared distinct.
"From further observations I find, that if you kill the Spider, and
immediately after extract the entrails, then inflate them by means of
a blow-pipe, you may preserve them tolerably well; you must clean them
on the inside no more than is sufficient to prevent moldiness, lest you
injure the colors, which certainly, in many kinds, depend on substance
that lies beneath the skin."
Scorpions, and all the Spider tribe, may be sent home in spirits, which
will preserve them perfectly, and when taken out and dried, they will
be found to have suffered nothing from their immersion. We have seen
some specimens sent up, after being sent home in spirits, which rivaled
any which have been preserved in a recent state. The animals of this
class are particularly liable to the attacks of insects, particularly
in warm countries, on which account the mode of transporting them
and keeping them in spirits is, perhaps, superior to all others. If,
however, they are set up in a warm climate, they should be well soaked
with the solution of corrosive sublimate, made according to the recipe
of Mr. Waterton.
For the setting up of this class, see the directions for preserving
insects.
INSECTS.
Every country of the world is replete with this extensive and
interesting class of beings, whose forms are infinitely diversified,
and whose species are the most numerous of any class in the animal
kingdom.
Before any attempt is made to collect insects, certain apparatus must
be provided, not only to enable us to secure them, but also to preserve
them after they are caught.
First, then, we must be provided with a quantity of wooden boxes, from
18 to 20 inches long, 15 to 17 inches wide; and two inches deep. These
should have well-filled lids, with hinges, and fastened by a wire
catch, or small bolt. The bottom should have a layer of cork, about the
sixth of an inch in thickness, which should be fixed down with very
strong paste, made according to our recipe; and also some wire nails,
to prevent it from springing. Over the cork should be pasted white
paper. The box should be anointed inside with oil of petroleum. If that
cannot be procured, make an infusion of strong aromatic plants, such as
cinnamon, aloes, thyme, laurel, sage, rosemary, or cloves, and wash the
inside with it. A small packet of camphor should be wrapped in a piece
of rag, and deposited in a corner of the box.
We must also be provided with a quantity of _Insect pins_, of different
sizes, corresponding with the size of the insect. The pins used for
setting should be longer than those which are taken to the field.
Bottles, with mouths from an inch and a quarter to two inches in
diameter, must also be procured, and these must be three-fourths full
of spirits, such as weak brandy, rum, gin or whisky.
HUNTING-BOX.--We must besides have what is termed a hunting-box, for
carrying in our pocket, when seeking after insects. This should be
made of strong pasteboard or chip, for lightness, or, if this is no
consideration, of tin. It must be of an oblong-oval shape, rounded at
the ends, for the convenience of the pocket. It should be from eight to
ten inches long, four to five inches wide, and two and a half to three
inches deep. It must have a layer of cork both in the bottom and top of
the lid, inside, for attaching insects to, when caught during the day.
The larger insects are placed at the bottom, and the smaller ones on
the lid.
THE ENTOMOLOGICAL.--We next procure a net, constructed similar to a
bat-fowling net. This is either made of fine gauze or coarse muslin;
it may either be green or white--the latter is the best for observing
small insects which may be caught; the green, however, is better
adapted for catching Moths. The net-rods should be made of hickory,
beech, hazel, or holly; they ought to be five feet in length, quite
round, smooth, and tapering to an obtuse point; the oblique cross-piece
at the point should be of cane, and fitted into the angular ferule; the
rod must be divided into three or four pieces, so that it may be taken
asunder and carried in the pocket; the upper part of each joint must
have a ferule affixed to it, for the purpose of articulating the other
pieces. Each joint should have a notch or check to prevent the rod from
twisting.
The net itself, must have a welting all around it, doubled so as to
form a groove for the reception of the rods. In the center of the upper
part or point it must have a small piece of chamois leather, so as to
form a kind of hinge; this must be bound round the welting, and divided
in the middle, so as to prevent the cross pieces from slipping over
each other; it shows about four inches of the gauze turned up, so as to
form a bag; there are strings for the purpose of passing through the
staple, to which the net is firmly drawn on each side. When the net is
used a handle is to be held in each hand.
If it is intended to take insects on the wing, by means of this net,
for which it is admirably adapted, it may be folded together in an
instant. If the gauze is fine enough, and preserved whole, even the
smallest insect cannot escape. It may be also applied in catching
Coleopterous Insects, which are never on the wing, as well as
Caterpillars. When used for this purpose the Entomologist must hold
it expanded under trees, while another must beat the branches with a
stick. Great numbers of both insects and larva will fall in the gauze,
and by this means many hundreds may be captured in a day.
Another method is to spread a large table-cloth under trees and bushes,
and then beat them with a stick. An umbrella reversed has frequently
been used for the same purpose. Bose, the celebrated naturalist, used
this last method--he held the umbrella in the left hand, while he beat
the bushes with the other.
THE HOOP OR AQUATIC NET.--This net is used for capturing Aquatic
Insects, which are either lurking at the bottom, swimming through the
liquid element, or adhering to plants. It may also be successfully used
in sweeping amongst grass and low herbage, for Coleopterous Insects,
and others which are generally to be found in such situations. The
socket for the handle may be made of such dimensions as will answer the
second joint of the Entomological net-rod, which will save carrying
another handle; or a walking-stick may be made to fit it.
A VIAL.--This may either be made of tin or crystal, and used for
collecting Coleopterous and other Creeping Insects. The mouth should
be nearly an inch wide, and a cork exactly fitted to it, in the center
of which must be inserted a small quill, to afford air, and inserted
about an inch beyond the cork, to prevent the insects from escaping.
If the bottle is made of tin, and of a larger size, a tin tube must be
introduced into its side, and terminating externally at the surface.
A DIGGER.--The instrument is either made of iron or steel, and is about
six or seven inches in length, fixed into a turned wooden handle. It
is used for collecting the pupae of Lepidopterous Insects, at the
roots and in the clefts of the bark of trees; and also for pulling off
the bark, particularly from decayed trees, under which many curious
and rare insects are frequently found. It is most useful with an
arrow-headed point.
SETTING NEEDLES.--Fitted into a small wooden handle, the needle itself
should be about three inches long, and about the thickness of a small
darning-needle slightly bent from about the middle. A straight needle
is used for extending the parts of insects; at one end of the handle is
the needle, and at the other a camel's hair pencil, which is used for
removing any dirt or dust which may be on the insects. The pencil may
be occasionally drawn through the lips, brought to a fine point, and
used for disposing the antennæ and palpi of insects of the minute kinds.
SETTING-BOARDS.--These must be made of deal board, from a foot or
fifteen inches long, and eight or ten inches broad, with a piece of
wood run across the ends, to prevent them from warping. They are
covered with cork, which must be perfectly smooth on the surface, with
white paper pasted over it. Several boards will be required, by persons
who are making collections, as some of the insects take a considerable
time to dry, so that they may be fit for introducing into a cabinet.
The boards should be kept in a frame made for the purpose. It should
consist of a top, bottom, and two sides; the back and front should
have the frames of doors attached by small hinges, and their centers
covered with fine gauze, for the free passage of air; the sides should
have small pieces of wood projecting from them, for the boards to rest
on; which should be at such a distance from each other that the pins
may not be displaced in pushing the boards in or drawing them out. The
frame should be placed in a dry, airy situation.
BRACES.--These are merely small pieces of card, cut in different forms,
attached to the butterfly and other insects. They are pinned down on
the insects, to keep their wings, etc., in a proper state, till they
acquire a set.
THE EGGS OF INSECTS.
The eggs of insects preserve their form and color in a cabinet, in
general, without much trouble. Swammerdam had a method of preserving
them when they appeared to be giving way. He made a perforation within
them with a fine needle, pressed out their contents, afterwards
inflated them with a glass blow-pipe, and filled them with a mixture of
resin and oil of spike.
THE LARVÆ, OR CATERPILLARS.
The easiest way of destroying the Caterpillar is by immersion in spirit
of wine. They may be retained for a long time in this spirits without
destroying their color.
Mr. William Weatherhead had an ingenious mode of preserving Larvæ. He
killed the Caterpillar, as above directed, and having made a small
puncture in the tail, gently pressed out the contents of the abdomen,
and then filled the skin with fine dry sand, and brought the animal to
its natural circumference. It is then exposed to the air to dry, and it
will have become quite hard in the course of a few hours, after which
the sand may be shaken out at the small aperture and the Caterpillar
then gummed to a piece of card.
Another method is, after the entrails are squeezed out, to insert into
the aperture a glass tube which has been drawn to a very fine point.
The operator must blow through this pipe while he keeps turning the
skin slowly round over a charcoal fire; the skin soon becomes hardened,
and, after being anointed with oil of spike and resin, it may be placed
in a cabinet when dry. A small straw or pipe of grass may be substituted
for the glass pipe.
Some persons inject them with colored wax after they are dried.
THE PUPA.
When the insects have escaped from their Pupa skin, the skin usually
retains the shape and general appearance it did while it contained the
insect. It is therefore ready for a cabinet, without any preparation
whatever. But if the animal has not quitted its envelope, it will be
necessary either to drop the Pupa into warm water, or to heat it in a
tin case before the fire; the former mode, however, is the best, and
least liable to change the colors of the Pupa.
METHOD OF BREEDING INSECTS.
BREEDING CAGES.--These must be made of oak, or other hard wood, as pine
is apt to kill the Caterpillars, from its smell of turpentine. The most
convenient size for a breeding cage is eight inches in breadth, four
deep, and one foot in height. It is not proper to place within a cage
more than one species of Caterpillar, as many of them prey upon each
other. Indeed, animals of the same species will devour each other, if
left without food. The Caterpillars of insects, for the most part, will
only eat one particular kind of food, so that it is better to have no
more than one sort in a cage.
There must be at the bottom of the cage earth to the depth of two
inches; this should be mixed with some fine sand and vegetable earth,
if possible, to prevent it from drying. The cages should be kept in a
cool cellar or damp place, because many insects change into the Pupa
condition under the earth; so that it would require to be somewhat
moist, to prevent the destruction of the animal. The shell or case of
the Pupa also becomes hard, if the earth is not kept moist; and, in
that event, the animal will not have sufficient strength to break its
case at the time it ought to emerge from its confinement, and must
consequently die, which but too frequently happens from mismanagement.
Some seasons are more favorable than others for the production of
Caterpillars, and to keep each kind by themselves would require an
immense number of cages, as well as occupy much time in changing the
food, and paying due attention to them. To obviate this, some persons
having large breeding cages, with a variety of food in them, which
must be cleaned out every two days, and fresh leaves given to the
Caterpillars; as, on due attention to feeding, the beauty and vigor of
the coming insects will much depend.
The Larvæ of insects, which feed beneath the surface of the earth,
may be bred in the following manner: Let any box that is about three
or four feet square, and two or three feet deep, be lined internally
with tin, and a number of very minute holes be bored through the sides
and bottom. Put into this box a quantity of earth, replete with such
vegetables as the Caterpillars subsist on, and sink it into a bed of
earth, so that the surface may be exposed to the different changes of
the weather. The lid should be covered with brass or iron net-work, to
prevent their escape, and for the free admission of air.
The young Entomologist should obtain a cabinet of about thirty drawers,
arranged in two tiers, and covered in with folding doors. There is
a great convenience in this size, as the cabinet is rendered more
portable, and at the same time admits of having another of the same
size, being placed above the top of it, as the collection increases,
without injuring the uniformity, and thus the drawers may be augmented
to any extent. It is immaterial whether the cabinet is made of mahogany
or oak; sometimes they are constructed of cedar, but seldom of pine,
or any other soft wood. Small cells must be made in the inside of the
fronts for camphor.
CORKING OF DRAWERS.--The simplest way to get the cork is to purchase
it of a cork-cutter, ready prepared, but it will be much cheaper for
the Entomologist to prepare it himself. In this case, it should be cut
into strips of about three inches wide, with a cork-cutter's knife,
to smooth the surface and to divide it. The strips should be fixed in
a vise, and cut to the thickness required with a fine saw; but grease
must not be used in the operation, as it will not only prevent the cork
from adhering to the bottom of the drawer, but will also grease the
paper which should be pasted on its surface. The black surface of the
cork should be rasped down to a smooth surface. After having reduced
the slips to about three quarters of an inch in thickness, the darkest,
or worst side of the slip should be glued down to a sheet of brown,
or cartridge paper; this should be laid on a deal board, about three
feet in length, and the width required for a drawer or box; a few fine
nails, or brads, must be driven through each piece of cork to keep it
firm and in its place until the glue be dried; by this means, sheets
of cork may be formed the size of the drawer. All the irregularities
are filed or rasped down quite to a level surface, and then polished
smooth with pumice-stone. The sheet, thus formed and finished, is glued
into the drawers. To prevent its warping, some weights must be equally
distributed over the cork, that it may adhere firmly to the bottom
of the drawer. When quite dry, the weights are removed, and the cork
covered with fine white paper, but not very thick. The paper is allowed
to be quite damp with the paste before it is placed on the cork, and,
when dry, it will become perfectly tight.
Insect cabinets should be kept in a very dry situation, otherwise the
antennæ, legs, etc., will become quite moldy. The same evil will ensue
if the insect is not perfectly dry before it is placed in the cabinet.
Should an insect be covered with mold, it can be washed off with a
camel's-hair pencil, dipped in camphorated spirits of wine; in which
case the insect must be dried in a warm airy situation before being
placed in the cabinet.
There should always be plenty of camphor kept in the drawers, otherwise
there is great danger to be apprehended from mites; where these exist,
they are easily discovered by the dust which is under the insects by
which they are infested. In which case they must be immediately taken
out and rubbed clean with a fine camel's-hair pencil, and well imbued
with the solution of corrosive sublimate, and then placed near a fire,
taking care, however, that too great a heat is not applied, as it will
utterly destroy the specimen. The Butterfly, Sphinx, and Moth tribes
are extremely liable to the attack of mites, and should, therefore, be
frequently examined.