The Parents' Review
A Monthly Magazine of Home-Training and Culture
Edited by Charlotte Mason.
"Education is an atmosphere, a discipline, a life."
______________________________________
Natural Science Recreations.
Beetles.
by Rev. A. Thornley, M.A., F.E.S.
Volume 3, 1892/93, pgs. 834-840
[Alfred Thornley, 1855-1947, "studied at Oxford, took holy orders and worked as deacon and
priest at parishes in Nottinghamshire. He had a wide interest in natural
history, but specialized in entomology and the study of Diptera. He was
relieved of most of his parochial duties, and worked with the County Education Department in training school teachers in natural history. Thornley was
Chaplain and Professor of Economic Entomology at Cirencester Agricultural
College for three years, before retiring to Cornwall. Thornley gave his collections, journals and notebooks to The Natural History Museum in 1946." Source]
It has been said that every man should have a hobby. I would rather say
that every man should endeavour to add something to the stock of
knowledge of his time. Many kinds of research, however, require much
previous training before they can yield results of any value; and only
he who has leisure and means can hope to achieve success in these
quarters. A simpler task, and one requiring less special preparation,
falls to the collector of natural objects, whatever they may be. A wide
field, too, presents itself for choice; and if I endeavour in this
paper to tell you something of the pleasure and instruction derived
from collecting beetles, I do not wish you to infer that the collecting
of these possesses any monopoly of advantage, or any superior pleasure
over the collecting of other things which Nature supplies. Shells,
plants, mosses, rocks, all exercise an exhilarating influence over the
mind. The love of natural history ennobled the lives of such men as
Robert Dick [1811-1866], botanist and geologist, of Thurso, and Thomas Edward [1814-1886], of
Banff, as well as numerous others; and as an incentive to studies which
this paper suggests, I would advise those who have not already done
so, to read the life of one of these patient searchers after Nature's
truth. The study of Natural History possesses the great advantage also,
of taking one out into the fresh air, thus tending to increase health,
and supplying an antidote to the evils resulting from sedentary
occupations or confining studies. Now, I labour under one great
disadvantage in my present subject, namely, the prejudice which exists
in the minds of some against beetles, nay, the very mention of the name
produces in them a feeling of creepiness and horror. "What! collect
beetles, cockroaches, and earwigs! ugh!" and, perhaps, some fair reader
wrings her hands with dismay. She considers those ugly black beetles
only fit to be trodden upon. Now, if I had time, I would set up a brief
on behalf of these greatly maligned insects, which, I am sure, would
lead you to respect them very much. However, at present, you must be
content to learn that the cockroach and the earwig are not beetles. I
admit, candidly, that both of our old friends just mentioned are very
like beetles, and therefore, I must try to give you a good reason--only
one out of many--why they are not put into the same class with the
beetles. Suppose we had opportunities of watching the development of
the eggs of the common earwig, and also those of some common beetle,
say the cockchafer. Please don't confuse this with the cockroach. One
morning we find that our earwig eggs have hatched; and what do we see?
A number of little creatures very like the parent earwig from which
they were derived. Just a few slight differences, and that is all. It
is a very pretty, and not at all an uncommon sight, to see these little
broods of baby-earwigs following their mother about, as chickens do a
mother-hen. In a short time, also, our cockchafer eggs hatch, and we
see resulting, a few little fat grubs, totally unlike their parent,
and, indeed, possessing no resemblance to a beetle at all. In the
natural state these grubs continue feeding at the roots of grass for
over the space of a year, and after this assume another state, which is
so remarkable and so typical of the whole tribe of beetles, that I will
shortly describe it to you. The grubs, having finished feeding, become
remarkably torpid. The body contracts, and slowly assumes a shape in
which the lineaments of the perfect insect may be perceived. This is
known as the pupa state. The word is Latin, and really means a "little
doll." It is well applied, for the resemblance to such a puppet in
swaddling-clothes is sometimes quite ludicrous. In this quiescent state
the future cockchafer rests for a period of some months; but at last
comes the mystic summons for it to awake from its long sleep; then,
working its way through the soil to the surface, the pupa bursts, and
out from it crawls the perfect cockchafer. A poor, soft, weak thing at
first, but in a few hours its tissues harden, and then, when the sun is
just setting in all the glory of the soft summer evening, it wings its
way to the highest branches of some elm or oak, there to rejoice in the
leafy wilderness for a season.
This perfect form is called the imago,
and in this state an insect never grows or alters at all. Many persons
believe that little flies grow into big flies, and little beetles into
big beetles. Here is a popular error. A little fly is always the same
size, and so is a little beetle. All the growing was done in the grub
stage. For this reason, size may form an important distinction between
two species; whereas, if the perfect forms of insects increased in
size, such a distinction would be useless. When next you see a little
fly and a big fly on your window, you may be almost certain that they
are distinct species. Now, these wonderful states through which so many
insects pass are scientifically called a "metamorphosis." In the case
of the beetle, you see how complete these stages are; but in the case
of the earwig they are scarcely apparent at all. Herein, then, lies one
great distinction between the order of insects to which our beetle
belongs, and that to which the earwig belongs. We might put it in this
way: an earwig is not a beetle, because it scarcely undergoes any
metamorphosis. It is the same with the cockroach. So now we may dismiss
them both, and return to our special study of beetles. Well, but we
must have one for our study, and rather a large one. Where shall we get
it from? Suppose you go out into the garden, and turn over a few
fair-sized stones. There he is now! Just look at that ugly black fellow
trying to make off as fast as he can. Don't be afraid; lay hold of him,
and put him in a bottle. Take him in, and put him into quite boiling
water. This is by far the readiest and best way to kill him, and not so
cruel as stepping on them, and leaving them crushed, and only half
dead, as some people do.
I would strongly recommend that children be forbidden to kill insects,
and be warned at all times of the cruelty of tormenting flies and other
insects. The method of killing suggested for scientific purposes is
practically instantaneous, but the water must be quite boiling. For the
sake of any "whose eyes grow tender over drowning flies," I suggest the
following method: Take a wide-mouthed bottle, provided with a
well-fitting cork. In this place a little cotton wool, then put into it
the insects to be killed, and pour on to the cotton wool a few drops of
ether, cork tightly up, and leave for half-an-hour or so. This will
certainly kill all small beetles, and any large ones which escape its
"hypnotic" influence, will be so still that they can be examined until
they come round, and then let go. It should be remembered, however,
that many beetles, particularly slow-crawling species, can be examined
in the living state, when the machinery has the advantage of being seen
in motion. If gently handled they take no harm. Bruised laurel leaf put
into the collecting bottle kills most beetles, I believe, in a painless
way; spirit of wine will do the same. We now proceed to examine our
insect. If you have a small pocket-lens it will greatly help you.
It would take a very long time to understand the marvellous and
complicated structure of a beetle, and I can only call your attention
now to the simplest parts of its anatomy. It will be sufficient if at
first, I ask you to notice that the insect consists of three
well-defined portions; the head, the thorax, or chest, and the body. To
the head are attached the antennae, or feelers. The form and structure
of these organs is of sufficient importance to give the name and chief
characteristic to some of the families, into which beetles are divided.
Thus, in the Clavicornia (club-horned), the antennae end in a more or
less distinct club. In the Rhynchophora, or Weevils, they are not only
clubbed, but owing to the great length of the first joint, they are
bent or elbowed: and this feature, together with the fact that the head
is produced into a long rostrum, or beak, makes this family one of the
easiest for beginners to recognise. Again, in the Lamellicornia, or
Chafers, a very singular form of antennae is found. The club in this
case is formed of from three to seven thin leaves or lamellae, a
feature which can be well seen in the common Cockchafer. In the
Longicornia (long-horned) the antennae are excessively long, sometimes
longer than the body of the insect; and lastly, in some families, these
organs are comb-like, saw-like, or perfectly simple. Now look at our
specimen once more, and note the powerful mandibles or jaws; also some
tiny organs, looking like very small, few-jointed antennae, these are
the palpi. Finally, noticing the prominent eyes, we shall have seen all
that is necessary, in such a superficial examination of the head. The
second portion of our insect is the thorax, or chest. Its shape is very
various, but the most important fact about it is, that all the six legs
of the creature are attached to its under surface, and the wings, and
wing covers, or elytra, to its upper. The third and last piece, is that
which I have called the body, more strictly the abdomen: a large soft
piece, consisting of a variable number of segments, and protected on
its upper surface usually by the elytra, though in many beetles these
are so short as to leave many segments of the abdomen exposed, and in
this case, the upper surface is more or less of a horny texture. In the
Staphylinidae [rove beetle], a family to which that fierce looking monster "the
Devil's Coach Horse" belongs, the elytra are exceedingly short, and
many persons would never suspect that these creatures were beetles at
all. Attached to the thorax are six legs: each leg consisting of three
well-marked portions. A femur, or thigh, a tibia, or shank, and a
tarsus, or foot. This latter consisting usually of from three to five
small joints. The whole leg is articulated with the under side of the
thorax, by a small joint, generally sunk in the latter and called the
coxa. Very frequently may be observed a small piece articulated between
the coxa and the femur; this is the trochanter. But it is to the
elytra, or wing covers, present in all beetles that the order owes its
name of "Coleoptera," or sheath-winged insects, and it is to some
peculiarities of the elytra that I must now very briefly call your
attention. Take your specimen in hand, and then with a pin gently
separate the wing cases. In most beetles this is easily accomplished,
and oftener than not, a beautiful pair of ordinary membranous wings
will be observed folded up beneath them. In a few beetles, the elytra
are soldered together, and then of course, the pair of membranous wings
is wanting. The elytra may be perfectly smooth, or covered with hairs,
or beautiful lustrous scales. But more frequently they are marked with
fine longitudinal grooves, called striae; and these latter are
frequently punctured; that is, present an appearance as if they had
been pricked with a needle, not quite through. It is very marvellous
the infinite variety of pattern produced by this devise of lines and
punctures. It renders the separation of species, otherwise very
similar, quite an easy task. But space will not allow of my lingering
any longer over these anatomical details, for I must conclude this
paper with a very brief account of the modes of capturing and
preserving beetles.
Now the latest catalogue of Coleoptera informs us, that there are 3243
species of beetle inhabiting Great Britain and Ireland. Many of these
are very small, and some are very rare. But this rarity is often due to
the want of collectors. The so-called "good localities" frequently
being so from the fact that, through the presence of an energetic
collector, the district has been systematically worked. Come with me on
an imaginary expedition. We will suppose it is that bewitching time of
the year when the hawthorn is in full blossom. We take in our pockets
several strong wide-mouthed bottles of different sizes, provided with
well-fitting corks, through which we have passed a piece of glass
tubing, or a quill, plugged with a little cork. It is a very simple
matter to pass an insect down the tube into the bottle, and much better
than having to remove an ordinary cork to which the insects frequently
cling, and may be lost at each removal. Inside our bottles we place a
few crushed laurel leaves, or at least a little moss, or even paper,
simply to afford a foothold for the little creatures and prevent them
from damaging one another by too great crowding together. A few tin
boxes, a large white calico net, for sweeping grass, flowers, or low
herbage; an old umbrella, into which we can beat trees and shrubs; and,
if we are likely to visit any ponds on the way, a small fishing-net of
muslin, and we shall be ready for any amount of beetles. Now we reach
our hawthorn blossom, and begin gently to beat the branches into the
open umbrella. What a shower of insects! Small beetles, spiders,
caterpillars, and bugs, and perhaps amongst them a beautiful longicorn
or chafer. By way of change, we now apply the sweeping-net to the long
herbage at the roadside, and we are again rewarded by a motley
collection of small and great, soldiers and sailors, little blue apions
and other small weevils, tiny jumping beetles of the family Phytophaga,
and numerous strange insect forms. But the stones! we must not forget
them. Gently turning over all the decent-sized ones, we obtain a
variety of active ground-beetles (Geodephaga) and cock-tails
(Staphylinidae). These must be put into a bottle by themselves, as they
have no compunction in eating up all smaller cousins. The laurel leaves
in the bottle should, however, keep them quiet for some time.
And so we go on; filling our bottles and tins. Nearly all the year is
good for beetle collecting--spring and autumn, I think, are the two
best seasons. In winter, moss from sheltered localities may be
collected in bags, and shaken out over white paper at home, when a
great number of small Coleoptera may be obtained. In autumn, it is
worth while to examine fungi, particularly those which are just
beginning to rot. Numbers of fine cocktails and Clavicornia may be thus
got. When home is reached, these beetles which are not already dead
must be killed, as intimated above, and carefully dried on
blotting-paper. The larger species should then be pinned (with a proper
entomological pin, if possible) through the right wing case. The
smaller species are mounted on nice, fine, thick cardboard with gum
tragacanth. It is best to make this several weeks before using, as it
improves greatly with a little keeping. Add a few drops of vinegar to
it to prevent the formation of mould. Now place your little beetle on
its back, hold it with a pair of forceps whilst you brush out, with a
camel-hair pencil, its legs and antennae. Then transfer it, right way
up, to a card on which you have placed a drop of your gum. Next, with a
needle, fitted into a wooden or cork handle, stretch out its antennae,
and set out its legs, so as to make it present just as natural an
appearance as if it were walking. If the beetle is very small, this
work will have to be done under a lens of low power, a task which
practice will soon perfect. When dry, the specimens can be cut off, a
small pin put through the card, and the insect placed in a corked box
or cabinet. Very small beetles may be mounted several together on one
piece of card. Each specimen should be numbered and a record kept in a
journal of the time, place, and circumstances of its capture. My space
is now all used up, and I will merely add, that I will gladly supply
more detailed information to any readers of this article who may desire
it. Further, I would gladly name any specimens they choose to send to
me.
Proofread by LNL, August, 2023
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