ALPHABET OF INSECTS.
JAMES RENNIJB, M.A.
PRICE If Vi
THE LIBRARY
OF
THE UNIVERSITY
OF CALIFORNIA
PRESENTED BY
PROF. CHARLES A. KOFOID AND
MRS. PRUDENCE W. KOFOID
SCIENTIFIC ALPHABETS.
NATURAL HISTORY.
INSECTS.
" Natural History may be fundamental to the erecting and
building of a true philosophy."
LORD BACON, Sylvae Sylvarum.
In forward preparation, uniform in Plan with the "Alphabet
of Insects,"
AN EXTENSIVE SERIES
OP
SCIENTIFIC ALPHABETS,
.FOR
THE USE OF BEGINNERS :
ON THE FOLLOWING SUBJECTS. /
Structure and Functions of
Plants
Flower Gardening (with a Con-
spectus)
Botany (Systems)
Spiders (with a Conspectus)
Kitchen Chemistry
The Weather
Astronomy (with a Conspectus)
The Races of Man
Birds (with a Conspectus)
Painting
Landscape Gardening
Light and Colours
Heat and Cold
Inductive Logic
Shells and Shell Fish (witb
Conspectus)
Geology
Architecture
Physics
The Structure of Man
The Functions of Man
Poisons and Antidotes
Engineering
Organic Chemistry.
&c. &c. &c.
ALPHABET OF INSECTS,
THE USE OF BEGINNERS.
BY JAMES RENNIE, M.A.
PROFESSOR OK ZOOLO&77"lflNa's COLLEGE, LONDON;
The Queen Butterfly in its various stages.
LONDON :
WILLIAM OUR, 14, PATERNOSTER ROW.
MDCCCXXXJI.
IXWDON :
IRY AND EVANS, PRINTERS,
BOUVBR1B STREET.
CONTENTS.
PLAN OF THE WORK • xi
THE WORD INSECT.
Divisions of an insect's body . .17
Distinguished from other animals . . ib.
THE SKIN OF INSECTS—
Resembles the bones of other animals . . 20
Layers of the skin . . .21
Colours of the skin . . . ib.
Pores of the skin . . ib.
Hair and down on the skin . . ib.
COMPOSITION OF THE SKIN.
Discovery and chemical properties of chitine . 22
THE HEAD IN INSECTS,
Pieces of the head . . lb.
Form of the head . . 23
Divisions not determined . . . ib.
Parts of the head . . ib.
Members of the head . . .24
The ears, the eyes, and the mouth . ib,
Junction of the head with the corselet . ib.
Position and motion of the head . . ib.
M368512
ii CONTENTS.
PAGE
THE CORSELET IN INSECTS.
Divided into three rings . . . 25
Law of proportion . . ib.
The breast plate . . . ib.
The breast prop . . . .26
Its uses .... ib.
The flanks, upper and under . 27
The wing scale . . . ib.
The horn scale . , . .28
Divisions of the back of the corselets . . ib.
The back plate ' , - , . ib.
The fore back plate ., *'1 ''(' l . 29
The mid back plate ^ . 30
The back scale .' •" . ib.
The bridle . ^ 'rKZ> if: . ib.
Mechanism to aid the muscles and wings . 32
Middle line of partition . . .33
Recapitulation . . . ib.
THE ABDOMEN IN INSECTS.
Its composition . . . t! . 34
Its rings . . ' t,<. ; . ib.
Arches of the back and of the belly v *, . ib.
Motions of the abdomen . ^ .^ . 35
Cord and pulley mechanism . j. j • ^-, . ib.
Muscles . . ^ .T.^ . 36
MEMBERS OF INSECTS.
Meaning of the term . . 37
• Objection to the term Appendage i*5**-*' . ib.
MEMBERS OF THE HEAD.
The Ears.
Their structure * ' .. . 38
CONTENTS. Ill
PAGE
Their insertion and connexion 38
Their direction . . .16.
Their length and proportion . . 39
Their form . . . ib.
Ears in male and in female insects . . ib.
The Eyes.
Structure of simple eyes . . 40
Structure of compound eyes . . 41
Singularity in night insects . . ib.
The Mouth.
Number of parts and law of proportion . 42
Wild theory of Lamarck . . . ib.
Reverse views of Savigny . . ib.
Mistakes of English naturalists . . ib.
Insects' mouths imperfect and " totally useless " 43
The upper lip . . • ib.
The upper jaws . . ib.
The under jaws, with their feelers, outer and inner ib.
The under lip, chin, feelers, and tonguelet . 44
Mouth in bees and in butterflies . .45
Mouth in two winged flies, gnats, and bugs . 46
MEMBERS OF THE CORSELET.
Legs and wings . . . .47
Law of proportion . . . ib.
The Legs in Insects.
Exactly six in number . . ib.
Jointings of each pair . . . ib.
Pieces of the leg, four in number . . 48
The haunch ... . ib.
The thigh . . . ib.
The shank . ... ibf
The foot . . ib.
a2
IV CONTENTS.
PAGE
The claw . . r-V r .49
The comb and suckers . it -.- i*« t; . ib.
The Wing* in Insects.
Their number . . , .• fn;«t ?i . ib.
First pair of wings . o;»'f . 50
Wing joint pieces . . ..*•>•: . ib.
Wing muscles . tii*,'*- > . ib.
Structure of the wings . j,»' . 51
Wing ribs or nervures . IY »V • • J . ib.
The edge rib and its hook s% .i .; . . ib.
The mid rib . vsff< tu^ . 52
The mid rib branch . fc*& frH'l i&.
The mid rib branchlets .iv-;>iJ . i6.
The inner rib ^ i.-' . > -*v«- . ift.
The lower rib J--A!V «??»a. . i^>.
The small marginal ribs . . f . t'6.
Terms for the circumference of the wing . 53
Areas of the wing . . .16.
Upper area . . • ib.
Mid area • 16.
Lower area . . a/./? . ib.
Meshes of the wing » \f) jirt . ib.
Base meshes . .. :r*f.&«« . ib.
Mid meshes . ,. uo-.*- '• . ib.
Outer meshes . .%'... .. . ib.
Streak, band, spot, and eyelet of the wings . 54
Fringes and tail of the wings < '*<> - . ib.
Texture of the wings v >% ^ . . ib.
Horny wings of beetles . j>'"*i . ib.
Leathery wings o-f locusts -» . .55
Winglet . . . 4i . ib.
The second pair of wings » '.. . . ib.
PAGE
Poisers . . . . .56
Wing bridles . . ib.
Clothing of wings . . . ib.
MEMBERS OF THE ABDOMEN.
Tail tuft . . . .57
Tail tweezers .* . . ib.
Ovipositors . . . .58
Sting . /;-'V . . ib.
Cleaning instrument . . ib.
INTERNAL ORGANS OF INSECTS.
The order in which these may be taken . 59
ORGANS OF DIGESTION.
Length of the organs in various insects . ib.
Their three layers . . ib.
Thehaus . . 60
Fountains of the mouth . . . ib.
Silk organs ;'.;.* is; . . . ib.
Division of the organs into six parts . . ib.
The gullet and its nervous ring . . 62
The crop or craw , ^j . ib.
Honey bag of bees and butterflies . . ib.
The gizzard ' .. ' . . ib.
Mistake of Swammerdam and Cuvier . ib.
The stomach . . 63
Bile vessels . . . . ^ ib.
Gastric vessels . . . 64
Outlet of the stomach . . ib.
Intestines . .. . ib.
The chyle gut .... ib.
The small gut and its functions . . . ib.
The blind gut . . . ib.
VI CONTENTS.
PAGE
The vent gut .. .. ' *m . 65
The vent . . . «.? . ib.
Offensive discharges — poison . >%4. >V.. ib.
Probable course of the chyle i a.t r . ib.
The fluid and solid portions .. «Ju . 66
Process of nutrition . . a-.- . ib.
ORGANS OF CIRCULATION..
The heart or dorsal vessel ,.. . 67
Its resemblance and difference compared with
the heart of other animals . . . ib.
No direct circulation of blood in insects . ib.
Extent, position, and form of the heart . ib.
Its structure . ,;xm .t«;y . ib.
Its contents . . ;.;£$•.>•' . ib.
Opinions of Audouin, Meckel, and Herold . 68
Description of the heart by M. Straus . ib.
Circulation of the blood traced }$*'''•*' • 69
Its supposed distribution and imbibition . 70
ORGANS OF BREATHING.
Insects have no lungs or nostrils . . ib.
. The spiracles « **••>•; . 71
Simple spiracles . . * 7; J • . ib.
Their number and position . ib.
Wings supposed to be spiracles ! ! ! i to ** . 72
Lips of the spiracles . . • a . ib.
Composite spiracles . * . «!•»:. ib.
The air pipes . . *!i. . ib.
The two windpipes and their branchings . . ib.
Structure of the air-pipes .. .. . 73
Structure of the air-cells . , . • ib.
Their ribs . . "! &.< [,j . . 74
Process of breathing . V « • • 75
CONTENTS. Vll
PAGE
ORGANS OF SENSATIONS.
Brain and spinal cord in man . • 75
Main nervous stem in insects . • ib*
The ganglionic system in man . . 76
A nerve-knot or ganglion described . . ib.
Ganglionic brain in insects . • ib.
Differs from the ganglia and from the brain in man ib.
Gullet ring and second ganglion . . . 77
Third ganglion and others . . . ib.
Number of ganglia . . ..«/;.
Structure of an insect ganglion „ . ib.
Nerves from the ganglia . . . ib.
Structure of the nerves . 78
Insects have not acute feeling . . 79
THE SENSES.
The sense of touch.
The ears mistaken for organs of touch . ib*
The feet, feelers, and hairs as organs of touch . 80
The sense of taste.
Sense delicate, but the organ unknown . ib.
The sense of smelL
The organ probably in the composite spiracles . ib.
Singular opinion of Dumeril . . ib.
The sense of hearing.
The ears often misrepresented . ib.
The sense of vision.
The nerves of the eyes . 81
The air-pipes of the eyes . . ib.
Ants not blind . . 82
ORGANS OF REPRODUCTION.
Insects differ from snails, and resemble birds . ib'
Singularities in bees, wasps, and ants . ib.
Vlll CONTENTS.
PAGE
Male insects never assist the female *>•:•• 82
Difference of the sexes in size and colour . ib.
Difference in wandering and stationary habits . 83
All female insects have eggs . -i.«;/y • *^«
Popular and theoretical errors refuted . ib*
Important discovery by M. Ehrenberg . . ib.
Insects' eggs proportionably large . . 84
Eggs traced in the body of the mother -«•: r . ib.
Eggs of the cockchafer . . ib.
Eggs of the louse . . ,>.-*<>.] . ib.
Egg-glue, and its use . . .85
Errors of the learned and the unlearned . . ib.
Miner, mason, and carpenter insects ro *i:;t • ib.
Curious instruments of female grasshoppers, saw-
flies, and gall-flies . . ., .*»• . ib.
Parasite or cuckoo flies . ^«£,./ . . 86
GROWTH OF INSECTS.
Abuse of the term Development . . 87
Metamorphoses or Transmutations more objectionable
than "Transformations" . . w* y ib.
EGGS OF INSECTS.
Form of eggs . ; w. ' ° . . ib.
Eggs of the gnat built into a boat . r ib.
Markings of eggs . . :t •«•«-• t gg
The shell expansible * *A' «V ; . ib.
Insects do not hatch their eggs * **£*^ •• V ib.
Proceedings of earwigs and ants > VUi ' . ib.
Absurd notions about blight *-u-u a 1-^>
Nobody says blight produces oxen or rooks . ib.
INFANCY OF INSECTS.
No single English word applicable . . 90
CONTENTS. IX
PAGE
Meaning of the term CATERPILLAR . . 90
Gooseberry and cabbage caterpillars . . ib.
Turnip fly and " worm i' the bud " • .91
Meaning of the term GRUB . . ib.
Not so definite as caterpillar . . ib.
Grubs of cockchafers and of weevils . . ib.
Turnip- fly grub and wire-worm . . . ib.
Meaning of the term MAGGOT . . 92
Blow-fly and bot maggots . • ib.
Cheesehoppers and crane-fly grubs . . ib.
Mawks and Gentles . • . ib.
The Latin term Larva fanciful and objectionable . ib.
ADOLESCENCE OF INSECTS.
Reason for adopting the term . . 93
How insects differ here from other animals . ib.
Preparatory nest or cocoon . 94
Covering besides the nest . . ib.
Gilt covering, and the term chrysalis . . ib.
Butterflies, moths, flies, beetles, and bugs , ib.
Terms used by Linna3us objectionable .-• . 95
ADULT STAGE OF LIFE IN INSECTS.
The fanciful Latin term Imago as objectionable as
the similar term Type . . . ib.
Injury to real knowledge from such fancies . 96
Abuse of the term Perfect . . . ib.
Absurd modern distinctions between perfect and
imperfect insects . . . ib.
Emergence of the adult insect . ib.
Peculiar appearance after emergence . . 97
Importance of the air tubes for inflation . . ib.
Adult insects never increase in size . . ib.
Examples from white butterflies and house flies . 98
Short life of adult insects . . . ib.
X CONTENTS.
PAGE
SYSTEMATIC ARRANGEMENT OF INSECTS.
Use of a system . . . ' . 99
Its logical convenience as a framework for facts . ib.
Misrepresented by the disciples of Linnaeus . ib
Systems lead to serious errors -->. ^ .^
The Trinity proved by the Trinarian System . ib.
Dangerous errors of the natural system in botany 100
Hibernian blunders respecting moths . . ib.
All systems imperfect . . . ib.
The terms kingdom, tribe, and family objected to ib.
Fashionable systems rejected /." i ^ • 101
System of Fabricius unnecessarily difficult . ib.
System of Linnaeus confused ' ' . . ib.
System of Baron de Geer partly adopted . ib.
Outline of a systematic arrangement of insects . 102
Conclusion '" 1" . 104
PLAN OF THE WORK.
THIS little Work is intended for those who
are desirous of beginning the delightful study of
INSECTS, or who, having begun, find their progress
interrupted by numerous difficulties. Among
these, one of the most prominent is, the want of a
plain and short outline of some of the leading sub-
jects of inquiry, by way of a basis on which to
proceed— a ground plan to work upon in rearing
a superstructure of knowledge.
There is no English work answering to these
views, and the French work of M. Audouin, though
very excellent in its way, is too brief and too tech-
nical.* I have therefore sketched the following
outline on a plan, which, I trust, will be found use-
ful, taking M. Audouin's book as a sort of founda-
tion, enlarging where I deemed it too brief, adding
where I found any thing important omitted, and
avoiding, as much as possible, the intermixing of
theory and hypothesis with facts.
* Resum^ d'Entomologie, 18mo, Paris, 1828.
Xll PLAN OF THE WORK.
In the three little volumes, published in the Li-
brary of Entertaining Knowledge, entitled INSECT
ARCHITECTURE, INSECT TRANSFORMATIONS, and
INSECT MISCELLANIES, I have introduced some of
the most interesting details and discussions re-
specting Insects ; but the plan of these works pre-
cluded my going into a regular elementary enu-
meration of parts and functions such as I have
here given, and which may accordingly be consi-
dered introductory to these three volumes.
The general rule of style which I always adopt,
is never to use a word derived from the Latin or
Greek when I can readily find one of Saxon origin,
not that it is possible to discard those derivative
words altogether — the English language would be
meagre indeed without such as have long been
naturalized and are well understood ; but as they
are not the basis of our language, we ought, I
think, to try to keep up our native words, and not
hunt after foreign terms which we do not indis-
pensably want. " Spotless," for example, I should
generally prefer to immaculate ; "across/' for trans-
versely ; u horny," for corneous; " forked/' for fur-
cate; and so on. Of all vulgarities, pedantic
vulgarity is the most offensive.
In giving names to things not previously named,
the Greek language, from its facilities in com-
pounding words, is usually resorted to, but this,
I think, is in many cases done without necessity,
as English, though not so easily compounded, may
PLAN OF THE WORK. Xlll
be often used with equal, if not greater, advan-
tage. The French in these cases gallicize the
Greek ; but this, except in chemistry and a few
other instances, appears to me in such bad taste,
that I hope never to see the practice followed in
England. " Whenever a Frenchman," says a
shrewd writer, " can get hold of a rag of Greek,
he instantly defiles it."* I have therefore ad-
mitted few, if any, terms not of English origin in
the text, and have consigned the Latin and Greek
terms to the notes.
The serious obstruction to knowledge caused by
the rage for multiplying newly invented words is
strikingly exemplified in the fact, that, of the "fifty-
two pieces composing the thorax," (corselet,) "Mr.
Kirby does not describe much more than twenty,
and yet uses about forty different words for them
in his nomenclature. "f These are the very words
of Mr. MacLeay, the author's most particular
friend. Now, with a book having forty newly coined
words for twenty things, how, I may justly ask, is
it possible that a student can make progress in
a science which has enough of difficulty arising
from the minuteness of the objects, without thus
taxing invention to increase them ? " The doubts
and difficulties/' says Audouin, " which are ex-
perienced at every step, in trying to comprehend
what pieces Mr. Kirby wishes to describe, suffici-
* Two Hundred and Nine Days, by T. J. Hogg, Esq. i. 226.
t Zoological Journal, v. 177»
XIV PLAN OF THE WORK.
ently prove (do they not ?) the total deficiency of
such a nomenclature, which is based on no philo-
sophical rule." (Annales des Sciences Nat. Few.
1832, p. HO, Note.)
Another leading feature of this little work is
the avoiding of the hypothetical theories which
are successively following each other in Natural
History, and which often vitiate the most valuable
observations of talented men. It is not a little
singular, that, while these theories are in a great
measure banished from other sciences, they should
now reign as paramount in this department as
alchemy and astrology did in the dark ages. I
have not here any room for details ; but shall
merely refer, for a proof of my position, to two
works which have appeared within twelve months,
one published under the patronage of Government,
entitled " Zoology of North America," Part II.,
in the introduction to which it is gravely suggested
that the doctrine of the Trinity may be corrobo-
rated by a Trinarian system of Animals ! ! ! — the
other, professing to relate to insects, entitled
" Sphinx Vespiformis," 8vo., London, a tissue of
the most incomprehensible fancies I ever looked
into.
The standard works upon insects, for those who
study philosophically, and look upon systems as
only a convenient aid subordinate to their inquiries,
are those of Aristotle, Redi, Malpighi, Valisnieri,
Swammerdam, Reaumur, Lyonnet, Lesser, Ray,
PLAN OF THE WORK. XV
Gould,Bonnet, Leewenhoeck, De Ceer, the Hubers?
Chabrier, Ramdohr, Audouin, Herold, Trevira-
nus, Leon Dufour, Straus- Durckheim, and a few
others, chiefly foreign, our English naturalists
being almost exclusively engaged in the inferior
departments of classing, inventing terms, and
theorizing.
The illustrations have been taken from the best
authorities — Audouin, Lyonnet, Straus-Durck-
heim, &c. Those of the parts of the corselet
have been reduced from the Zoological Journal,
No. 18, by the liberal permission of the publisher,
G. B. Sowerby, F. L. S.
The next of this series connected with Zoology,
will be the ''ALPHABET OF BIRDS/' comprising
an outline of their comparative anatomy and
physiology, to accompany " A CONSPECTUS OF
BRITISH BIRDS."
Lee, Kent, June 10th, 1832.
ALPHABET OF INSECTS.
THE WORD INSECT.
THE first thing to be learned on beginning to
study the branch of Natural History of which I shall
here treat, is to know how an insect differs from other
animals.
The -word Insect means "cut into," and every in-
sect accordingly appears with divisions as if cuts had
been made in the body ; one just behind the head,
and another behind the corselet, as may be seen in a
bee or a fly ; and the whole body besides is composed
of rings, and it is on this account only that modern
writers use the term insect.
These cuts divide the body of an insect into three
parts, the head, the corselet, and the abdomen ; and
any animal in which these parts are not found distinct
is not an insect. Consequently a spider, awoodlouse,
a shrimp, or a crab, is not an insect, because none of
these have more than two of the divisions; while
the earthworm, the leach, the snail, the slug, and
the oyster, are not insects, because they have none of
these divisions distinct.
THE WORD INSECT.
Parts of an insect shewn in the African cricket ; a, the head
carrying the ears, /, /, with the eyes at their base ; b, c, d, the
corselet separated into three pieces ; the fore corselet, b, carrying
the fore or first pair of legs, i, i; the mid corselet, c, carrying
the second pair of legs, ht h, and the first pair of wings, g, g; the
hind corselet, d, carrying the hind legs, k, k ; and the second
pair of wings, /, I ; e, the abdomen.
Caterpillars, grubs, maggots, gentles, mauks, meal-
worms, bloodworms, and wireworms, from being in a
state of infancy or youth, do not in general possess the
three divisions distinct, as they all do when arrived
at their last state of full grown or adult insects.
With respect to other marks of distinction, it may
be proper to mention that insects have no bones, no
THE WORD INSECT. 19
brain, no veins, no branched arteries, consequently no
circulating blood ; and do not breathe by the mouth,
but through air-pipes in the sides. All insects have
exactly six legs, though some butterflies have the
first pair so short as not to be readily observed; and
many caterpillars have, besides their six legs, as
many as ten to sixteen members similar to legs, for
the purpose of clinging and climbing.
B 2
20 THE SKIN OF INSECTS.
THE SKIN, OR CRUST, OF INSECTS.
IT seems indispensable to every plant and every
animal to have a skin, to cover and protect the more
sensible parts in the interior of the body. The skin
in insects, however, appears still more important, from
its having to fulfil, in some degree, the office of the
bones in other animals.
The skin, therefore, is usually hard, like horn, or
tough, like leather or parchment; though in some
species, and also in the first stage of a very considera-
ble number, it is thinner and softer than the human
scarf skin.
In all cases, the skin furnishes a series of levers, or
points of attachment and support to the muscles, by
which every motion of the insect must be made. Un-
like the skin of animals, therefore, that of insects is
made up of various pieces, more or less closely jointed
or joined like the various bones of animals. Each
bone of other animals, moreover, is well known by a
distinct name ; but the pieces of the skin in insects
have only been recently examined, and the few names
already given to the pieces are not well determined,
and still in much confusion.
A talented French naturalist, M. Audouin, thinks
he has reason to conclude that there is always, from
the moment of exclusion from the egg, a determinate
number of pieces in every insect, probably thirteen,
which are either distinct or two or more of them
united ; that various species differ in having some of
the pieces large and others small, or altogether want-
ing ; and that when any piece is found larger, other
pieces near it will be proportionably smaller.
The human skin is formed of three layers, the scarf
COMPOSITION OF THE SKIN. 21
skin(1), the mucous net workf2), and the inner skin(3).
In insects only two layers are usually obvious, the
inner somewhat resembling the mucous net work of
the human skin, and, like that, being the membrane of
colour.
The colours of insects are exceedingly various;
black prevails among beetles and flies; white among
caterpillars, grubs, and maggots, which feed under
cover; green among caterpillars which feed on
leaves; grey and dusky among moths; while the
colours of butterflies are usually bright white, yellow,
blue, and red, in diversified shades and markings.
The terms usually given to the colours of insects in
our modern English books pretending to science, often
exhibit the most offensively pedantic taste, besides
being frequently unintelligible. Thus we meet with
griseous, for grey; ochraceous, for buff; luteous, for
yellow ; miniatous, for scarlet ; niveous, for snow
white ; and numerous vulgar barbarisms of the same
kind, which would not be tolerated in any other
science.
In many insects pores may be detected in the skin,
and probably these exist in all.
A considerable number of insects are clothed with
hair or down, inserted, as in other animals, into the
inner skin. It seems useful in keeping bees warm ;
in preventing the water from soaking into water-
beetles ; and may also possess electrical uses which we
cannot trace.
COMPOSITION OF THE SKIN.
IF the student of insects understand any thing of
Chemistry (4), it may be useful to mention, that the
(1) In Latin, Epidermis. (2) In Latin, Rete mucosum.
(3) In Latin, Cutis vera, or Corium.
(4) An " ALPHABET OP CHEMISTRY " will make one of this
series of little beoks.
22 THE SKIN OF INSECTS.
skin of insects is very complicated in its composition-
M. Odier, on analysing the wing cases of the cock-
chafer, found — 1 . Albumen ; — 2. Extractive, soluble
in water; — 3. A brown substance, soluble in potass
and insoluble in alcohol ; — 4. A coloured oil, soluble in
alcohol; — 5. Carbonate of potass, phosphate of lime,
and phosphate of iron; — 6. A particular principle,
constituting one fourth of the weight of the wing
cases : this principle he named Chitine.
It is chitine which in reality forms the outer frame
or crust of insects. If an insect, such as a cockchafer
or a dung beetle, be plunged into a solution of potass
and exposed to heat, the crust of the insect is not
dissolved and does not change its form. The only
change it suffers is the loss of colour ; all the muscles
and intestines disappearing, the crust, consisting of
chitine, alone remaining.
Chitine differs therefore from horn, hair, and the
human scarf skin, which are soluble in potass. It is,
besides, soluble in hot sulphuric acid, does not become
yellow by the application of nitric acid, and burns
without fusion or losing its form. It does not contain
azote. It consequently resembles woody fibre more
than any animal substance.
THE HEAD.
THE head of insects, though it be represented
as composed of three or four pieces, does not in
general show the least trace of divisions or rings, like
the rest of the body : but, because the rest of the
body is composed of rings or pieces, it is conjectured
by theory, that the head is also so composed, though
we cannot perceive the divisions.
In the newly hatched insect, the head is often
joined to the bo'dy, as in spiders, without any obvious
division,which is always apparent in the adult insect;
THE HEAD. 23
but, even in the young state, it is usually harder,
smoother, and of a different colour from the body.
In animals which have a bony skull the head is
always more or less round ; this being both the most
capacious form, and the most difficult to injure by
accidents, — circumstances so important in protecting
the brain ; but in insects which have no brain, the
head, though in most cases round, is often of various
shapes ; as somewhat square and angular in the
stag-beetle, flat and wedge-like in wasps and bees,
and nearly triangular in some of the bugs. In the
weevil and scorpion fly, again, it is long and pointed,
while in some beetles and- four-winged flies it tapers
backwards into a long neck (J).
Minute naturalists are not yet agreed about the
divisions of the head, and M. Audouin first says, " it
can be demonstrated that it is composed of several
segments ; " and again he .says, " it is composed of
rather solid walls, most frequently presenting no trace
of junction, so that it appears at first view quite
simple, though an experienced eye soon discovers it
to be the result of several segments — the number not
yet determined, — united together." That is, as it
appea,rs to me, a theorist, accustomed to find that the
bones of a skull can be separated, readily imagines
junctions of pieces in the head of an insect, though he
acknowledges them to be imperceptible.
The head of insects, like that of other animals, con-
sists of the crown and forehead, (both of which M.
Meckel objectionably calls the skull), and the face;
but the extent of the cheeks is seldom very distinct.
It is not so with the mask(2), as we may call it, a part
which on the one side is jointed with the front or face,
and on the other with the upper lip, which it covers;
(1) In Latin, Collum.
(2) The mask is termed by the French, Chaperon ; in Greek,
24 THE SKIN OF INSECTS.
and when the upper lip is wanting, (as it is in some
species), the mask performs its office.
in all insects, two horn-like members project from
the forehead — very long, with many joints, in butter-
flies; very short in the house fly; and prettily feathered
in male gnats, and in many male moths. These I
shall venture to call ears (!), as it is most probable,
though not distinctly proved, that they are the organs
of hearing. In front, and at the root of the ears, are
two eyes ; but many insects have besides several other
eyes on the forehead, as maybe seen in bees, who have
three of these frontal eyes. Insects have no organ
similar to the nose in other animals, as they breathe
entirely by the air-pipes in the sides. The mouth is,
for the same reason, not employed either for breathing
or for uttering sounds, but simply for feeding. It is
very different in form and structure from the mouth
of other animals.
The head is joined to the first ring of the corselet,
either by a neck, by a simple membrane, or by means
of a socket hollowed into the form of a funnel.
The natural position of the head is various. In
grasshoppers and dragon flies, it is vertical ; in most
beetles, it is somewhat slanting, and almost horizontal.
It is very moveable in the common fly and the dragon
flies, so that it can be turned almost round, as on a
pivot. In many other insects it is immoveable, as in
the grasshoppers. In others, the head can be folded
down, or drawn back, so as to remain concealed, or
nearly so.
THE CORSELET.
THE middle portion of the body in insects, always
obviously distinct from the head before, and from the
(1) In Latin, these organs are termed Antennae.
THE CORSELET. 25
abdomen behind, I shall terra the corselet ('). Unlike
the head, this part is composed of several distinct rings
and pieces, which have but recently received names,
and been studied. Most of the names invented by our
English authors are confused, inappropriate, and bad.
In following M. Audouin, I shall endeavour to be as
plain and simple as I can.
The most natural division of the corselet is into
three rings or segments, though these are sometimes
very distinct, and sometimes intimately united. These
three rings, beginning from the neck, may be termed
the fore-corselet , the mid-corselet, and the hind-cor-
selet(2), which three being united, form the corselet.
It will be convenient to consider, that the whole cor-
selet, as well as its three rings, has a breast, two sides,
and a back.
The student must be warned, that, among the nume-
rous species of insects, these several parts are found to
be very variable in size ; and, agreeable to the interest-
ing law, that as one part is enlarged, another is pro-
portionally diminished, it is not unusual for a par-
ticular part to be exceedingly minute, or wholly
wanting, if a contiguous part be comparatively very
large.
Taking the whole corselet, and beginning at the
breast, we find a piece which may be appropriately
termed the breast-plate (3), and is found in all insects,
forming sometimes a large, sometimes a small piece,
in some species very distinct, as in several water-
beetles, but in others so intimately united to the con-
tiguous pieces, that the joining is imperceptible. The
breast-plate forms the middle of the breast in all the
three rings of the corselet, and for the sake of more
minute distinction, it may be considered as divided
(1) In Latin, Thorax.
(2) In Latin, Prothorax, Mesathorax, Metathnrtue.
(3) In Latin, Sternum, which is inaccurate.
26 THE SKIN OF INSECTS.
into the fore breast-plate, the mid breast-plate, and the
hind breast-plate (').
On the inside of the breast-plate, in the interior of
the breast, is another singular piece, usually jointed
with the hinder and inner end of the breast-plate. It
varies much in form, but frequently resembles a Y,
and is hence called the prop, or Y piece, by the
French naturalists (2). This is always present in each
of the three rings, and, like the breast-plate, may be
considered as the fore breast-prop, the mid breast-
prop, and the hind breast-prop (3). It extends in some
cases within the head, and in others, as in the tree-
hoppers, within the abdomen, and was then termed
by Reaumur the scaly triangle.
The chief use of the breast-prop, seems to be to
afford an attachment and lever to the muscles which
move the fore legs; very evident in the singular
breast-prop of the mole cricket : and, according to
Audouin and Marcel de Serres, to protect the nerves,
by separating them from the gullet, stomach, and
heart. The hind breast-prop has often attracted atten-
tion from its singular trident-like form.
The fore corselet, under side ; a, b, the breast-plate ; c, c, the
under flanks.
1) In Latin Prosternum, Mesosternum,
(2) In Latin Furca, or Entothorax.
(3) In Latin Antefurcu, Prof urea, and Postfurca.
THE CORSELET. 27
The side pieces, which may be called the flanks,
consist of one on each side, in each of the three
rings of the corselet, joined to the breast-plate, — in all
three pairs, which we may call the under flanks (l) ;
and other three pairs, usually united to the former,
above and behind, sometimes even resting on the
breast-plate itself, may be called the upper flanks (-).
These have always a constant relation with the
haunches (3) of the ring to which they belong, and
sometimes share in forming the circumference of their
socket, being jointed with them by means of another
small piece, which M. Audouin calls Trochantine.
The mid breast-plate ; a, the breast-plate ; b, bt the mid under
flanks.
Besides these six pairs of flanks, there is generally,
though not always, a very small piece, in relation
with the wings and the under flank, always resting
on the latter, sometimes going along its fore border,
but sometimes, becoming free, it passes either before
or above the wing. It may be termed the wing scale(4).
Along the fore border of the under flank, sometimes
of the breast-plate itself, and even of the upper part
of the body, the opening of an air-pipe or spiracle
may often be observed surrounded by a small piece,
(1) In Latin Episterna. (2) In Latin Epimera.
(3) In Latin Coxa. (4) In Grseco- Latin Parapteron.
28 THE SKIN OF INSECTS.
often of a horny texture, which may be called the
horn scale ('). It is not always present, for the spiracle
itself is often closed; hut when it is found it is im-
portant, as a good guide in the comparison of the
other parts.
It is proper here to remind the student, that, when
he examines an insect, he ought to look for all these
pieces, just as, in examining a rat, he ought to look for
the gall bladder ; but he must not be disappointed if
he do not find all the pieces, as some may be wanting,
as the gall bladder is in the rat ; and the accounting
for such variations opens a fine field of philosophical
research.
The hind breast-plate ; a, its upper flank ; b, its under flank :
r, the plate itself; d, the breast prop.
Having thus gone over the various pieces which
compose the breast and the sides of the corselet, we
may next turn to the upper part of it, which may be
termed the back plate (2), extending from the neck to
the abdomen. In rei'erence also to the division into
three rings, and beginning at the head, we may call
(1) In Latin Peritrema.
(2) In Latin Tergum thoracis.
THE CORSELET. 29
the first, the fore back plate; the second, the mid
back plate ; and the third, the hind back plate (*).
The back of the whole corselet in a wasp (Polistes Billardieri).
a, the fore back plate ; b, c, the mid back plates ; c, the mid
back scale ; e, g, the hind back plate j e, the first piece ; /, the
second piece ; g, the hind back scale ; d, d, the sides of the
mid back plate ; h, the fourth piece of the hind back plate j t, t,
the under flanks ; k, k, the wing scales of the second pair; /, /,
the wing scales of the first pair ; m, m, haunches of the hind
legs ; n, part of the abdomen; o, o, p, pt g, q, the sockets of the
two pair of wings ; r, r, the spiracles for breathing; s, the cord
for the pulley.
Each of these, in many instances, is composed of
four pieces. The fore back plate is thus found to
consist of four pieces in locusts and crickets, being
in these insects large, and the breast small, according
to the law of proportion. In beetles, and most winged
insects, however, only two pieces can be readily dis-
(1) In Latin Tergum prothoracis, Tergum -mesothoracis, and
Tergum metathoracis.
30 THE SKIN OF INSECTS.
tinguished, on account of the intimate junction. The
fore part (') is generally concealed within the body.
The fore back plate, front and side views; a, the first piece,
or collar ; b, the second piece.
The mid back plate is, in like manner, composed of
four pieces. The second of these (2) is important, from
its always jointing, by means of side pieces, (very dis-
tinct in the ruby tail fly), with the wings. The third
is what may be called the back scale (3), and is usually
somewhat triangular in form. Jn some of the plant
bugs, this part extends over the wings, wing cases, and
the border of the abdomen. Another piece of the mid
• back plate is usually quite concealed in the body, or
sometimes so intimately joined to the former, as scarcely
(1) In Latin Prtescutum. (2) In Latin Scutum.
(3) In Latin Scutellum.
THE CORSELET. 31
to be distinguishable. Sometimes it is distinct and
free. It has been termed the bridle (!).
The mid back plate, front view, a, the fore part ; b, the
second piece ; c, the third piece ; d, d, the supposed side pieces
of the second piece ; e, the internal third piece ; /, /, the wing:
scales of the first pair ; g, g, joint bones of the first pair of wings
above the sockets.
The hind back plate is also composed of three pieces,
the first being often concealed within the body, but
obvious in bees and wasps. The second is occasionally
composed of two pieces, as in some water beetles, but
these are intimately united in the stag beetle. The
third piece is divided by a channel lengthwise, \*hich
has led to the mistake of considering it as two separate
pieces. The fourth piece is very conspicuous in the
common fly, and also in the cockchafer ; but in obe-
(1) In Latin Franum.
32 THE SKIN OF INSECTS.
dience to the law of proportion, it is exceedingly small
in crickets, grasshoppers, and locusts.
The hind back plate, front view ; a, the first piece ; b, the
third piece, the second not being: obvious ; c, the fourth piece ;
d, d, the under flanks ; e, e, the wing scales of the second pair ;
/, /, the breathing spiracles ; g, the cord for pulley.
In order to render this brief description of the
corselet complete, it may be necessary to mention
that, on the inner surface of the plates, there are cer-
tain remarkable inequalities of surface, and even
some distinct parts observable, besides those already
described. Amongst these are occasional horny
ridges, (*) always formed by the junction of two con-
tiguous pieces; and, when they can be detected, they
are excellent guides for discovering the boundaries of
two pieces, which cannot be distinguished on the out-
side. They serve for the attachment of muscles.
When these ridges are on the outside, (2) they often
assist in the mechanism of a joint, such as those of
the wings.
Other small pieces are found in the inside of the
corselet, sometimes in the form of flat plates raised upon
(1) In Latin Apodem.ee insertionis.
(2) In Latin Apodema articulationis.
THE CORSELET. 33
a foot stalk, and wide at top, like certain mushrooms,
such as those which Reaumur found in the abdomen
of the treehopper, and termed cartilaginous plates.
Like the former, they either serve for the attachment
of muscles (*), or assist in the mechanism of the wing
joints (2).
It is farther to be remarked, that if the corselet, as
well as the head and abdomen, be cut exactly in half,
lengthwise, each of the pieces and organs on each
side will correspond as exactly as our own two hands,
or our two nostrils ; a very remarkable fact.
Recapitulation.
The corselet, then, according to this statement,
consists of
f Fore breast plate,
V Fore breast prop,
FORK CORSELET ^ Two under flanks,
I Two upper flanks,
v Fore back plate, four pieces.
f Mid breast plate,
I Mid breast prop,
_ _ _, J Two under flanks,
MID CORSELET < Two upper flanks>
I Two wing scales,
* Mid back plate, four pieces.
HIND CORSELET
/ Two wine: scales.
r pieces.
In all thirty-six pieces ; or, if considered as divided
lengthwise in the middle, there will be fifty-two
pieces.
(1) In Latin, Epidemee insertionis.
(2) In Latin, Epidemee articulationis.
C
34 THE SKIN OF INSECTS.
THE ABDOMEN IN INSECTS.
WE are obliged to use this very objectionable term
for the third and last division of the body, which is
more or less closely united to the corselet. The ab-
domen may be described to be that part of the body
which succeeds the corselet, consisting in most cases
of a certain number of rings, without any jointed
members for locomotion, and uniformly enclosing a
portion, sometimes a very small one, of the intestines.
It is formed by a series of very short hollow
cylinders or rings, united with each other by a joint,
by a membrane, and sometimes by an intimate junc-
tion, the exact line of which is not obvious. Some-
times the rings slide into one another like the tubes of
a telescope.
Each of these cylinders is called a ring or seg-
ment (1), and is sometimes composed of a single piece,
sometimes of two half cylinders, whose two borders
usually come into contact. In other cases they do not
touch at this point, but remain free, and one more or
less overlaps the other, as in bees.
Each ring is virtually composed of two principal
portions, which, when they can be distinguished, (this
is not always possible) take the name of arches (2). The
upper, is called the arch of the back(3); the under,
the arch of the belly (4).
In the flea, the bed bug, and other insects without
wings, as well as in grubs and caterpillars, where the
joining of the corselet with the abdomen is not so
obvious, the latter may always be known by the legs
never being jointed with it.
When the back of the abdomen is covered, as in
(1) In Latin, Segmentum. (2) In Latin, Arcus.
(3) In Latin, Arcus tergi. (4) In Latin, Arcus ventris.
THE ABDOMEN. 35
beetles, by the wing-cases, it is softer and more flexi-
ble than the belly ; in other cases the reverse.
In beetles, and some other insects, the abdomen is
joined to the corselet without any joint to permit
motion ; while in bees, wasps, and most two- winged
flies, there is a very obvious joint, consisting of a
hinge, scooped out in the first ring for the purpose of
receiving a projecting part of the fourth piece of the
hind-back plate of the corselet, arising from between
the thigh sockets of the third pair of legs.
The termination of the hind back plate ; a, joint of the abdo-
men j b, b, sockets of the thighs of the hind legs.
There is besides, in the corselet, a distinct opening
or hole, (of a triangular form in bees), to give passage
to the broad tendon (l) of a muscle from the abdomen,
and to serve as a pulley (2), over which it may play. In
proportion as this muscle contracts, it accordingly pulls
the abdomen upwards, which falls downwards again
when it is relaxed.
Wasps, bees, earwigs, and many other species, have
the power of moving the abdomen in various direc-
tions, as a whole, and of bending and curving it as
a dog does his tail, all of which motions are performed
by means of muscles attached to the inner surface of
the rings.
The muscles or cords by which every motion is
performed are very numerous, as may be seen from
(1) In Latin, Funiculus,
(2) In Latin, Trochlea.
c2
36 THE SKIN OF INSECTS.
those of the caterpillar of the goat moth, traced with
incredible skill, patience, and accuracy by M. Lyon-
net, to whom I am indebted for this figure.
Muscles of the caterpillar of the goat moth ( Cossus ligni-
perda} ; with the two main air-pipes running along each side,
and the heart with its six pairs of pyramidse wings in the
middle.
THE EARS. 37
MEMBERS OF INSECTS.
THE word member lias been chosen here from its
involving no theoretical fancy, as the term Appendage,
used in modern books, always seems to do. I apply
the term member to any part of an insect, either
jointed upon the body, or not appearing to make a
portion of its surface, such as the legs, wings, and
ears, as well as the eyes ; and, by slightly extending
the term , it may also include the tail-fork of the ear-
wig, and the sting of the bee.
In describing the members, I shall follow, in the
same order as before, the head, corselet, and abdomen.
MEMBERS OF THE HEAD.
IT will be most convenient to consider the several
members of the head, in the order in which they ap-
pear most conspicuous to the eye, beginning with the
ears, and proceeding to the eyes, the feelers, the lips,
and the jaws.
The Ears of Insects.
The members which I here venture to call the ears (!),
though not quite proved to be the organ of hearing,
are uniformly two in number, standing out from the
head, upon which they are jointed and moveable in
a socket (2), by means of a ball or pivot (3).
Supposing the head to be composed of a ring made
up of determinate pieces, similar to the corselet, the
(1) In Latin, Antennae, which means placed before, and was
applied by the Romans to the sail-yard of a ship.
(2) In Latin, Torulits.
(3) In Latin, Bulbits.
38 MEMBERS OF INSECTS.
ears would be found to arise like the wings, from the
junction of the upper flanks with the back or rather
crown plates.
The ears are composed of minute cylinders or rings
successively added to each other, to the number of
thirty in some butterflies; and thus forming a tube,
which encloses nerves for sensations and muscles for
moving, as well as air-pipes and cells.
As to their insertion or connexion, they are always,
according to M. Audouin, placed near the eyes, be-
fore, behind, above, below, between, or even appa-
rently within these. Sometimes their bases are near
together, or united, and sometimes considerably dis-
tant.
As to their direction, they are stiff or flexible,
straight or nodding, parallel or diverging, spiral or
not spiral; and they are in some species carried
always forward, in others backward, or towards the
sides, and sometimes folded up or drawn into a sheath.
Various forms of the ears.
- THE EYES. 39
As to length, they are very long compared with the
length of the body, in some moths and beetles, and
very short in the house fly ; but their length does not
depend on the number of the joints, for they may be
long, when composed of only three or four pieces, and
short, when composed of ten or more pieces.
As to form, they are either cylindrical, conical,
bristle-shaped, awl-shaped, spindle-shaped, forked,
branched, feathered, tiled, beaded, (like a neck-lace),
pectinated, (like a comb), serrated, (like a saw), prism-
shaped, downy, hairy, or bristly. Their tips again are
either pointed, knobbed, clubbed, hooked, triangular,
leaved ('), (as in the dung beetle), forked, blunt,
awned (2), abrupt, or perforated.
In the males of moths, gnats, and some other in-
sects, the ears are in all or most cases more orna-
mented with feathers, hairs, or sculpture, than in the
female, in which the ears are plain.
The Eyes of Insects.
In the larger animals, there is only one sort of eyes,
but insects have two sorts, veiy different in structure,
which have been called simple and compound, there
being always two compound eyes (3), placed near the
base of the ears on each side of the forehead or face ;
but the simple eyes(4) vary in number, and are placed
higher up, usually on the crown of the head, as in
(1) In Latin, Lamellate.
(2) In Latin, Aristatee.
(3) In Latin, Oculi compositi.
(4) In Latin, Ocelli, or, very objectionably, Stemmata.
40 MEMBERS OF INSECTS.
the bee, where the simple eyes are three in number,
and placed in a triangle.
The upper portion of a bee, showing the two compound eyes
with their facettes at the base of the jointed ears : together with
the three simple eyes in form of a triangle on the crown.
We do not meet with simple eyes in all insects, but
no adult insect is without compound eyes. The num-
ber of simple eyes is usually three. Each is composed
of, 1. an outer membrane, hard, transparent, and
formed of a single piece (l) ; 2. a layer of a viscous or
clammy substance (2), immediately behind the first,
which determines the colour of the eye, being black
in bees, white in crickets and grasshoppers, and red,
yellow, or green in some caterpillars; 3. a rather
thick membrane (3), seemingly composed of a tissue of
net- work, whose meshes are very closely set ; and 4.
a nerve from the ganglion of the head, very small,
which penetrates to the inside of the outer mem-
brane, where it spreads out.
Compound, composite, shagreened, or facetted
eyes, are so named from being made up of a great
(3) In Latin, Cornea. (2) In Latin, Pigmentum.
(3) In Latin, Chor aides.
THE EYES. 41
number of minute eyelets, not unlike the six-sided
facettes of crystals. They are always immoveable,
differing in this from the eyes of larger animals.
Each of the little eyelets or facettes is very similar
in structure to one of the simple eyes already de-
scribed. According to Professor Miiller, of Bonn, the
composite eye of the dragon fly may be divided into
two parts ; one above and behind of a reddish colour,
with the eyelets twice as broad as those of the other
in front and below, which is greyish.
When the whole composite eye is cut into, we find,
1. the outer transparent membrane (a) ; 2. the larger
or clammy-coloured matter (6); 3. abroad belt, orange-
coloured before, and black in front (c) ; 4. a second
belt within the first, deep black (d) ; 5. the ganglion
of the nerve, which, when slightly pressed, is seen to
be composed of rays of fibres, or threadlets (e), one of
which probably passes to each eyelet.
. The cellular tissue, and the clammy-coloured sub-
stance, are found wanting in some species of night
insects ; and, according to Treviranus, there is in the
cockroach, (a night insect), behind the outer mem-
brane, a mass of a dark violet colour, composed of
numerous little pyramids, upon which the nerve is
spread in the form of fibres.
42 MEMBERS OF INSECTS.
The Mouth in Insects.
Following the generalizing views of M. Audouin, in
considering the head composed of similar parts to one
of the three divisions of the corselet, the mouth will
occupy the place of the breast-plate and the two
under flanks ; and taking each of these three as com-
posed of two pieces, there would be in the mouth, by
supposition, six pieces ; and this in fact is the number
of pieces found in a great number of species, though
not in all ; for, by the law of proportion, when a part
is much enlarged, a contiguous part is either very
small, or altogether wanting.
Notwithstanding the mouths of insects are thus
composed of a determinate number of pieces, their
structure both appears to be, and is, very different, —
for example, in a bug, a butterfly, a bee, and a
beetle,— owing to the difference of form, as well as to
the difference of junction in the several pieces.
M. Lamarck, who seems first to have had a glimpse
of the general uniformity in the number of pieces in
the mouth of all insects, at once leapt to the singular
and untenable conclusion, that bugs, through process
of time, got rid of the joinings that made their mouths
into a tube, and successively improved themselves
into beetles with good moveable jaws. M. Savigny,
reversing this process, thinks the jaws of the beetle
degenerated into the suckers of the butterfly and the
bee.
Many of our English naturalists, from being far
behind in logic and generalizing, and therefore in-
competent to take advantage of Continental researches,
so admirable when they are stript of theory, forthwith
conclude, that all insects, without free, moveable jaws,
or having any of the six pieces wanting, have imper-
fect mouths. One English naturalist in particular,
by a gross misconception of Savigny's meaning, re-
THE MOUTH. 43
presents the mouths of sucking insects as " totally
useless;" and thence concludes, " they can do no in-
jury to agriculture/' a conclusion as false as the former
is impious.
I have stated this in order to prevent misconcep-
tion, which, from the imperfection of terms, is but too
apt to mislead a genuine field observer, and is cer-
tain to mystify and bewilder a compiler or a cabinet
naturalist.
Comparing the jaws of an insect with those of
man, or with the bill of a bird, we find that while the
motion of the latter is upwards and downwards, the
motion of the former is forward from the sides, Ac-
cording to M. Audouin, who follows M. Savigny, the
mouth of an insect consists of the upper lip, a pair
of upper jaws, a pah- of under jaws, and an under lip.
1. The upper lip (J) is a flat, usually horny, plate,
joined horizontally to the lower part of the face, and
closing the mouth.
2. The upper jaws (*), one on the right and another
on the left, resemble, in eating insects, a large horny
tooth, more or less curved, often indented, andjointea
into the sides of the head immediately below the upper
lip, being moveable, and without any pieces attached
to them, as is the case with the under jaws. In some
moths the upper jaws are exceedingly small, with a
part as if scooped out in each.
3. The under jaws (3) are also two in number, and are
jointed into the right and left of the inner cavity of the
mouth, immediately below the upper jaws ; they re-
semble the upper jaws in moving from the sides for-
ward ; but are seldom so strong, being rather mem-
branous than horny, particularly at the tips ; they also
differ in being jointed, while the upper jaws are
solid.
(1) In Latin, Labrum. (2) In Latin, Mandibute.
(3) In Latin, Maxillae.
44 MEMBERS OF INSECTS.
Usually, at the place where the horny texture ends,
and the membranous begins, there is, on each of
the under jaws, a remarkable little member, in
form of a thread, composed of from four to six joints,
commonly tipt with a part less homy than the rest,
jointed upon a stem or footstalk that supports it, and
furnished with hairs. These jointed members are
called feelers (*), though the term is objectionable,
because their use is not well ascertained.
Sometimes the inner front of the lower jaw forms a
sort of acute lobe, or even a large scale, furnished at
the tip with a hook, and resembling the upper jaws.
In that case, the outer division of the upper jaw takes
sometimes the form of a case orarched shield (2) ; some-
times it constitutes a second feeler which is short, and
inserted within it. These are called inner feelers (3), to
distinguish them from the outer, and longer feelers(4),
described above.
The only organs in other animals similar to these
feelers are the whiskers in the cat, the mouse, the seal,
the night-jar, and other birds which feed on insects ;
and the beardlets in the cod, the barbel, and other
fish.
4. The under lip (5), which closes the mouth below,
is not unlike a second pair of upper jaws united, on
their inner side, and covered in the greater part by a
horny projection called the chin (6).
• Each of the halves of the under lip carries a feeler
smaller than those of the under jaws, and composed
of four or more joints. The projection beyond the
chin is called the tonguelet (7). In many insects there
is found a small piece (8) on each side, arising in the
(1) In Latin, Palpi. (2) In Latin, Galea.
(3) In Latin, Palpi interni. (4) In Latin, Palpi extern*.
. (5) In Latin, Labium. (6) In Latin, Mentum.
(7) In Latin, Lingula. (8) In Latin, Paraglossa.
THE MOUTH.
45
fauces, resting upon the tonguelet, with a tip like a
small ear.
Parts of the mouth in a beetle, a, the upper lip ; b, the upper
jaws ; c, the under jaws, with two pairs of jointed feelers; d, the
under lip, with the short tongue in the middle, the chin below
this, and a pair of jointed feelers.
In bees, the under jaws are rather long, encasing
the sides of the lip, and these, being united, form a
sort of sucker, moveable at the base. Cuvier mistook
the under lip for the tongue.
In butterflies and moths, the upper jaws and the
upper lip are very minute, the under jaws immoveable
at the base, and form two lines which are united and
form a long tube rolled up spirally. It would be no less
incorrect to call this the tongue, as it has been called
byFabricius, Latreille, and Cuvier, than it would be to
represent it as an imperfect mouth, as has been done
46
MEMBERS OF INSECTS.
by our English naturalists from gross blundering and
fatuity.
Parts of the mouth in a day flying moth (Zygeend]. «, the
upper lip ; b, b, the upper jaws ; c, c, the under jaws in form of
a sucker carrying the jointed feelers at their base ; d, the under
lip with the tonguelet in the middle, and the jointed feelers on
each side.
In two- winged flies and gnats, the upper lip forms a
case, the two pairs of jaws are in form of bristles, and
were mistaken by Latreille for feelers, while the under
lip forms a tube.
Parts of the mouth in a gnat, a, b, the upper lip and upper
jaws carrying the jointed feelers ; /, c, d, the under jaws and
tonguelet ; e, the under lip.
THE LEGS. 47
In bugs, the under lip forms a long sheath ; the
edges, bending downwards, are shaped into a hollow
canal, which receives the two pairs of jaws, in this case
formed like long bristles, the two middle ones pro-
bably acting as piercers, while the other two probably
assist in sucking.
MEMBERS OF THE CORSELET.
THE members which belong to the corselet are ap-
propriated to locomotion, and are of two sorts. One
sort are jointed to the under pieces of each of the three
rings of the corselet ; these are the legs (!) : another
sort are jointed into the upper pieces of the mid cor-
selet and the hind corselet — never to the fore corselet ;
these are the wings (2).
Here the law of proportion is observed to regulate,
as it always does, the relative size of the members,
and the pieces on which they are jointed. When the
legs, or a pair of them accordingly are very short, the
corresponding pieces of the corselet are very small ;
and when the wings are small or wanting, the cor-
responding pieces are small or undivided.
The Legs in Insects.
Insects have exactly six legs, though the first pair
or the fore legs, are in some butterflies so small as
scarely to be detected. Millepedes, centipedes, and
wood-lice, which have more than six legs, are not
strictly insects.
The fore legs, or first pair, are jointed into the
joinings of the breast-plate with the under flanks in
the fore corselet, and are always directed forwards.
(l) In Latin, Pedes. (2) In Latin, Ales.
48 MEMBERS OF INSECTS.
The mid legs, or second pair, are jointed with the same
pieces in the hind corselet.
Each leg may be considered as made up of four
principal pieces— the haunch, the thigh, the shank,
and the foot — enclosed in a horny or membranous
skin, containing the necessary muscles for moving the
joints.
The haunch (!) is various in form, being short and
small in most beetles, while it is large in wasps and
grasshoppers. In lady-birds it is round ; in cock-
roaches it is flat. It is made up of three pieces (2), two
next the corselet working in the socket (3), and the
third (4) jointed to the thigh, but apparently without
independent motion.
The thigh (5) is the second principal piece, and is
always comparatively long and generally bulged, but
flat. It can only be moved backwards and forwards
and not sideways. In leaping insects, and in those
which dig and burrow, the thigh is always long, strong,
and muscular.
The shank (6) is the third principal piece of the leg,
and is generally flat and about the same length as
the thigh, but more slender. In the hind legs of
swimming insects, the shank is often fringed. Upon
the upper end and sometimes the middle, moveable
spurs (7) are frequently jointed or fixed.
The foot (8) is the fourth principal piece, with which
the leg ends. It is composed of five smaller pieces in
a great number of species, but in some cases only from
one to four, and in others, the number varies in the
several pairs of legs on the same insect. Two muscles,
one above and one below, have been detected in each
of these pieces.
(1) In Latin, Coxa.
(2) In Latin, Trochantina and Rotula.
(3) In Latin, Acetabulum. (4) In Latin, Trochanter.
(5) In Latin, Femur. (6) In Latin, Tibia.
(7) In Latin, Calcaria. (8) In Latin, Tarsus.
WINGS OF INSECTS. 49
The most remarkable part of the foot, is the tip
Eiece termed the claw (!), which is wanting in the fore-
;gs of some butterflies and other species. Each foot
has usually two claws, but in some insects there is
only one, and in others, there are four and even six
on one foot. The claws are very various in form
according to the uses intended.
In the two-winged flies there are, between the
clawsjfrom two to three thin plates (2), outwardly convex
and toothed like a comb, and used for cleaning the
body and wings. At the base also are suckers, or,
as Mr. Blackwall thinks, spunges, containing a sort of
glue, which enable flies and other insects to walk up
glass against gravity.
The leg of an insect, a, the haunch ; b, the thigh ; c, the
shank, with a forked spur j d, the foot, with five joints.
The Wings in Insects.
The wings in insects are four, sometimes two, in
number, and are uniformly jointed upon the upper
(1) In Latin, Unguis. (2) In Latin, Pectines.
50 MEMBERS OF INSECTS.
flanks, and the back plate of the corselet, — one pair
uniformly on the mid corselet, and the other uniformly
on the hind corselet.
The upper or fore wings^), which may he also called
the greater or first pair, are always jointed upon the
two upper flanks, and the hack plate on each side of
the mid -corselet, and of course near the centre of
gravity, being balanced on the one side by the head
and fore corselet, and on the other by the abdomen
and hind corselet.
Somewhat like the human wrist, which is composed
of a number of little bones, the wing joint in insects
has small horny joint pieces (2), to the number of seven
in the first pair, of various size and figure, but all
united by a membrane, and jointed on the one side
with the wing, and on the other, with the back plate
and upper flank.
These joint pieces move the wings by means of
three muscles, — the first divided into two portions
where it is attached to the inside of the corselet ; but
these unite into a single tendon, and are fixed into
one of the joint pieces. When this muscle contracts,
it lowers the base of the wing and consequently raises
the tip.
A second muscle is also fixed within the corselet,
and is attached to another of the joint pieces. This
muscle lowers the inner edge of the wing and gives
it a sort of pendulum-like motion.
A third muscle is similarly placed, and acts in con-
cert with the two first.
The preceding description applies to the wings of
bees and wasps ; while in two-winged flies there are
two sets of muscles : one set placed lengthwise for
(I) In Latin, Alee anterior es.
(2) In Latin, Epidemee.
WINGS OF INSECTS.
51
lowering the wings, and another placed aslant and
across these for raising the wings.
o, wing of dragon fly ; b, wing of bee ; c, wing of a house fly.
In general, the wings may be said to be composed
of two membranes united together by means of horny
lines, which are variously termed veins, nervures(1),
and wing bones, though not quite correctly. I prefer
the term rib (2).
The wing rib is not to be considered as a bone, but
as a horny and nearly solid tube enclosing air-pipes (3)
for the purpose of expansion. The number and dis-
position of these ribs, which may be reckoned about
seven, varies greatly in different groups of insects.
In bees, wasps, two-winged flies, and butterflies,
beginning at the upper edge of the wing, we find it
formed by a strong rib which may be termed the
fore-rib (4), rendered remarkable in some butterflies for a
hook at its base which serves as a pulley for. the tendon
of a muscle
At some distance, often about the middle of the
(1) In Latin, Neuree. (2) In Latin, Costa.
(3) In Latin, Trachea.
(4) In Latin, Costa anterior or Radius.
D2
52 MEMBERS OF INSECTS.
wing, and somewhat parallel to the fore rib, runs
another also usually strong, sometimes the strongest
of all the ribs, — which may be termed the mid rib ('),
for though not quite in the middle of the disc of the
wing, it is for the most part nearly so at its base.
In many insects, particularly bees, butterflies, moths,
and dragon-flies, the fore and mid rib join near the
upper edge, at some distance from the tip, forming a
small opaque horny plate, probably serving as a re-
servoir for air or fluid, which may be termed the
rib-spot (2).
From near the base in the mid rib, there is often
given off a branch which runs between it and the
fore rib, sometimes, as in butterflies, so large, that it
may be mistaken for the mid rib itself. It may be
termed the mid rib branch (3). It is wanting in bees.
On the lower side of the mid rib several branchlets
are given off, which go to unite with other branchlets.
These branchlets may, if necessary, be numbered
1, 2, 3. &c., or lettered a, 5, c, &c.
The next leading rib in the wing may be termed
the inner rib (4), and is usually divided near the base
into two, sometimes three or four, branches. In butter-
flies, the division takes place about the middle of the
wing.
Near the under edge of the wing is another rib,
which may be termed the lower rib (5), between which
and the edge, are in some groups, one or more small
ribs (6).
These several ribs and their branches, (in some
groups so numerous as to give the whole wing the
appearance of lace or net work), by inclosing portions
of the wing, form what may be termed areas (7), and as
(1) In Latin, Costa media or Cubitus.
(2) In Latin, Stigma. (3) In Latin, Costa mediastina.
(4) In Latin, Costa interna. (5) In Latin, Costa inferior.
(6) In Latin, Costulte marginales. (7) In Latin, Areoe.
WINGS OF INSECTS. 53
it is of some use to attend to these, in describing the
wings, I shall point out the principal areas, premising
that a wing may ,be said to have a base (!), where it is
joined to the corselet; an upper edge(2) running from
the base to the fore tip(3), an outer edge (4) running
from the fore to the hind tip (5), and a lower edge (6)
from the hind tip to the base.
What may be termed the upper area (7) is the space
inclosed between the mid rib with its branches and the
upper edge.
The space inclosed between the mid rib and the
inner rib, with its branches, may be termed the mid
area. In butterflies(8), this space is somewhat oblong
and triangular, without any cross ribs.
The space inclosed between the mid rib and the
lower rib, or between the lower rib and the under
edge, may be termed the lower area (9).
The irregular space, occupying the outer edge;
all the wing, indeed, not included in the three other
areas, may be termed the outer area (10).
These several areas are further divided into smaller
areas, or, as they may well be called, meshes, which
form beautiful lace-work in the dragon flies and
others of the same group.
According as they are in the base, the middle, or
the outer edge, these may be termed base meshes(H),
mid meshes(12), and outer meshes(13).
The other parts of a wing necessary to be at-
tended to in descriptions, are chiefly coloured mark-
ings, particularly on the wings of butterflies, such as
(1) In Latin, Basis. (2) In Latin, Margo anterior.
(3) In Latin, Apex anterior. (4) In Latin, Margo exterior.
(5) In Latin, Apex inferior. (6) In Latin, Margo inferior.
(7) In Latin, Area superior. (8) In Latin, Area media.
(ft) In Latin, Area inferior. (10) In Latin, Area exterior.
(11) In Latin Cellula basilares. (12) In Latin, Cellula mediae.
(13) In Latin, Cellules exterior es.
54 MEMBERS OF INSECTS.
astreak('), aband(2), aspot(3), an eyelet(4), a sprink-
ling^5), &c. The outer and lower edges, are, in but-
terflies, moths, and some other insects, furnished with
fringes(6), and sometimes with a tail(7).
Markings of the wings of butterflies and moths.
With respect to texture, the first pair of wings in
beetles are so horny and stiff, that they have no close
resemblance to what are called wings in other insects.
They are indeed less adapted to flight than to cover
the second pair in a state of repose, and to balance
the body, perhaps, by their weight in flying. Some-
times indeed these horny wings, usually called wing
cases(8), cannot be separated on the back, in which case
the second pair of wings is either very small or
(1) In Latin, Striga. (2) ID Latin, Fascia.
(3) In Latin, Macula. (4) In Latin, Ocellus.
(5) In Latin, Irroratia. (6) In Latin, Cilia.
(7) In Latin, Cauda. (B) In Latin, Elytra.
WINGS OF INSECTS. 55
wanting. The term wing cases is quite appropriate,
so far as function is considered ; but it is important to
know that these wing cases in beetles occupy the
same place, and are jointed in the same manner, as
the first pair of wings in bees.
The leathery wings of locusts, crickets, and grass-
hoppers, and the half leathery wings of tree bugs,
and some other insects, are also similar in their rela-
tive situation to the first pair of wings in bees.
In the base of this first pair of wings, there are
found in the common fly, some beetles, and other
insects, a pair of small scaly members, dependent on
the larger wings, and appropriately termed winglets(1).
It is a mistake to consider these apart from the wings,
for they are always jointed into the back plate of the
mid corselet, never into the hind corselet, and united
at the base to the wing ; and often the separation of
one of them from the wing cannot be traced. It is
sometimes double, that is, two to each wing, like
a bivalve shell. It does not, as has been supposed,
produce the buzzing of flies.
The second pair of wings (2) are always, like the first
pair, jointed with the back plate and upper flanks of
the hind corselet. They are in most respects similar
to the first pair, as in the joint pieces, which are only
six instead of seven, the ribs, the areas, and the parts
of the circumference.
It is worthy of remark that, except in dragon flies,
earwigs, some beetles, and a few other insects,
they are commonly much smaller than the first pair,
but in all cases, following the law of proportional rela-
tion, to the parts of the corselet upon which they are
jointed.
In the common fly, and others similarly constructed,
there arises exactly from the same part of the hind
, (1) In Latin, Alulae. (2) In Latin, Aloe posterior es.
56 MEMBERS OF INSECTS.
corselet as the second pair of wings, a pair of small
members, shaped somewhat like a drum-stick, and
protected above by the winglet. These have been
called poisers (1), or balancers, and are supposed by
some to aid in balancing the body, by others to pro-
duce buzzing, by beating on the winglets, neither of
which opinions is proved. The law of proportion
proves them, as M. Audouin thinks, to be the second
pair of wings, which he proves by the fact of the
poisers only occurring in insects having no second
pair of wings.
In moths, the second pair of wings are each fur-
nished near the base with a sort of slender, but stiff,
horny hook, somewhat curved, which is fixed into a
projection of the first pair, by way of bridle (2).
In wasps and bees the second pair are bridled to
the first pair by minute hooks, in form of an S along
the upper edge.
The wings of some insects are clothed with hair,
and others, as butterflies and moths, with a sort of
feathery scales (3), which appear in the microscope of
very various forms. These scale feathers are placed
over each other like the tiles of a house, are the
coloured part of the wing, and easily come off on
being touched, in the form of dust.
The feathery scales from the wings of butterflies and moths,
magnified to shew their various forms, — from Reaumur.
(1) In Latin, Halteres. (2) In Latin, Frenum.
,. (a) In Latin, Plumulce.
57
MEMBERS OF THE ABDOMEN.
THE only members in this portion of an insect's
body, are situated upon the two last rings, and are
very various in form and use. Insects, having no
spine, like animals furnished with bones, have no
tail, at least similar in structure to that of the dog or
the horse ; but in many moths there is a hairy brush,
which is termed the tail(!), on the last ring. Its use
is not apparent in the males, while in the females the.
hair is plucked out to cover their eggs, by an instru-
ment similar to a pair of tweezers, also placed on the
last ring of the abdomen. In the scorpion fly the tail
is jointed.
In earwigs there is a forked member (2) on the last
ring, the blades of which are moveable, and which
are said to be used for folding up (rather, I should
think, for unfolding) the wings, which are for the
most part concealed under the short wing cases. A
somewhat similar member, but the blades crossing
each other as scissors, is found in the male snake fly.
In the rove beetles are long, narrow, stiff members ;
and the dragon-flies, leaf-like members on the last
ring, absurdly called a sting, but whose use is not
well ascertained, any more than the use of the long
bristles jointed into the last ring in the day fly, and
shorter ones in the cockroach, and some crickets and
grasshoppers.
In other instances, there are long members in the
last ring, somewhat similar to a brad-awl, and used
for the purpose of boring holes to deposit the
eggs. These are peculiar to females, and are termed
(1) In Latin, Cauda. (2) In Latin, Forceps.
58 MEMBERS OF INSECTS.
ovipositors^). They are sometimes hollowed into a
tube for the egg to pass along, and sometimes solid.
In bees, wasps, and some other insects, there is a
weapon used for attack and defence, termed the
sting (2), which can be drawn within the abdomen
•when it is not used. It is composed of a sheath,
darts (3) barbed at the point, and a poison bag at the
base for poisoning the wound which it makes.
In the grub of the glow-worm, I discovered a
singular instrument on the last ring, composed of
gristle-like rays, in form of a funnel, covered with a
clammy adhesive substance, and capable of being
extended and contracted. The grub employs it to
clean every part of the body.
a, The last ring of the abdomen of a bee opened, shewing the
sting in its sheath ; b, the sting of a bee magnified to show the
barbed darts ; e, cleaning instrument of the grub of the glow
worm open ; d, the same shut.
(1) In Latin, Ovipositores.
(2) In Latin, Aculeus. (3) In Latin, Spicula.
ORGANS OF DIGESTION. 59
INTERNAL ORGANS OF INSECTS.
HAVING thus taken a brief, but, I trust, an intelli-
gible survey of the outside of the body in insects, the
student may be supposed to be partly prepared to
examine the various organs within the body. It will
be convenient, for this purpose, to begin with the
organs employed in the digestion of the food, and
then pass on to those employed in breathing, sensa-
tion, and reproduction.
t
ORGANS OF DIGESTION.
IT is remarkable that the length of the organs
of digestion in insects, measuring from the mouth to
the vent, is, as in the larger animals, proportioned to
the sort of food. Vegetable food, being more crude,
or not so like the properties of the animal body,
requires more preparation to turn it into nourishment ;
and hence, insects, and other animals which feed on
vegetables, have their organs of digestion of great
length, much longer, indeed, than the body, in which
they wind in many folds. Animal food requiring
less preparation, the insects which feed on it have
their organs of digestion short, and of the same length
as the body. In all cases they consist of three layers,
the outer membranous, the middle muscular, and the
inner mucous.
60 INTERNAL ORGANS.
When the food has been taken into the mouth and
bruised, or chewed by the jaws when those are
moveable, or sucked up when they form a sucking
tube, it passes on to the haus or entrance (') of the
gullet, and thence to the stomach and intestines as in
the larger animals.
In man, the food is mixed, during the process of
chewing, with a peculiar fluid supplied from several
glands or fountains situated near the mouth. In
insects, similar fountains (2) have been described by
Ramdohr, Leon Dufour, and others. They are most
obvious in sucking insects, and when a fly cannot suck
a bit of dry sugar, it has been observed to moisten it
with this fluid.
The organs (3) which furnish the silk, spun by the
silk- worm and other caterpillars, are similarly situated
with the preceding, and perhaps are the same organs.
The most complicated organs of digestion, (found,
of course, in insects feeding on vegetable matter,)
may be described under six divisions, the gullet, the
crop, the gizzard, the stomach, the intestines, and
the vent.
(1) In Latin, Fauces or Pharynx; in Scotch Haus.
(2) In Latin, Sialisteria. (3) In Latin, Sericteria.
ORGANS OF DIGESTION.
The organs of digestion in two different beetles. Fig. l, a
garden beetle (Carabus). Fig. 2, a churchyard beetle (Blaps).
a, the jaws and feelers; b, the head; c, c, the saliva vessels ;
d, the gullet, very short in Fig. 1 ; e, the crop, wanting in Fig.
1 ; /, the gizzard, wanting in Fig. 1 ; g, the stomach, large and
convoluted in Fig. 1 ; h, h, h, the bile vessels long, and nume-
rous ; i, the small intestine ; k, the blind gut ; /, the vent ; m, m,
the excrementary vessels.
62 INTERNAL ORGANS.
The gullet^) varies much in length, being sometimes
very short, and sometimes reaching to the abdomen,
or even within it, but it is more generally the length
of the fore corselet within which it is lodged. When
there is no crop or gizzard, it ends in the stomach.
At its upper end, it is surrounded by a nervous ring,
from which two branches go off and unite at the
lower part of the body.
The crop (2) or craw is a bulging out of the gullet
into a sort of pouch, which, on the outside, can sel-
dom be distinguished from the gizzard ; but, on the
inside, it is found destitute of horny projections, and
its texture more membranous than muscular. When
large, it is often seen with folds or plaits. It con-
stitutes what is called the honey bag of the bee, and
it is in it that insects have the fluids, often offensive,
which they discharge when caught, as is observed
in many beetles. In butterflies and other sucking
insects, it is placed on one side of the gullet, and not
in the line of the stomach. Its contents have, there-
fore, to be returned into the mouth before they can
reach the stomach. The crop is not found at all in
many instances.
The gizzard(3) succeeds the crop, and is more mus-
cular in structure, and furnished on the inside with
moveable horny projections, most probably employed
in bruising the food. These horny pieces are of
various figures, and placed in various directions,
sometimes like a brush, sometimes like a comb ; and
just above the entrance of the stomach they nearly
close the passage, forming a sort of valve, which will
only permit minute portions of the food to pass.
Swammerdam and Cuvier are mistaken in thinking
insects which have a gizzard, such as grasshoppers,
(1) In Latin, (Esophagus.
(2) In Latin, Ingluvies ; in German, Speisesack.
(3) In Latin, Ventriculus callosus.
ORGANS OF DIGESTION. 63
chew the cud. The chewing motion which deceived
them, I have found to be the process of cleaning the
feet and the ears. The gizzard is not found in all
insects.
The stomach^) is composed of thin, soft, extensible,
membranes, usually cylindrical in form, but some-
times with bulgings and contractions, and sometimes
forked, the entrance (2) being at one of the forks. One
remarkable circumstance is, that, in many insects, the
outer surface is covered with a number of teat-like
points, similar to the finger of a glove, containing
fluid which they discharge into the stomach. These
may be termed vessels (3). They vary much in size
and number, and are not found in all insects. Dif-
ferent opinions are held respecting them by Cuvier,
Marcel de Serres, and Leon Dufour.
In all insects, we believe, there are vessels called
bile vessels (4), consisting of several membranous tubes,
filled with a peculiar fluid, bitter, and usually brown
or yellow, but sometimes limpid, supposed to be
similar to bile, though we find nothing like the liver
for preparing this bile, which is probably, therefore,
as M. Gae'de thinks, prepared in the vessels them-
selves. These vessels float in many convulutions in
the abdomen, one end being sometimes free and the
other fixed, and sometimes both ends fixed, and
giving rise to a sort of arch or curve. Sometimes
these are inserted into the stomach near its outlet (5) ;
in others, one end goes into the stomach, and the
other into the blind gut. Their number varies from
two, which are found in the rose-chafer, to four,
found in beetles and common flies ; to six, found in
butterflies, and to even one hundred and fifty (pro-
(1) In Latin, Ventriculus chyliftcus, or Duodenum.
(2) In Latin, Cardia. (3) In Latin, Villi.
(4) In Latin, Vesiculi biliarii. (5) In Latin, Pylorus.
64 INTERNAL ORGANS.
bably mere branches of two fundamental ones), found
in bees, wasps, and dragon-flies.
It is in the stomach that the food is converted, by
means of the digestive fluid, from the gastric vessels
and the bile, into a pulpy mass, called chyle, if we
may follow the analogy of other animals.
The outlet (l) of the stomach is in insects furnished
with a valve to prevent the too rapid passage of the
chyle into the intestines.
The intestines (2) form an extended portion of the
organs of digestion, which may be divided into four
parts, the chyle gut, the small gut, the blind gut,
and the vent gut.
The chyle gut(3), which is always found in large
animals, is seldom, in insects, different from the small
gut. When it is distinguishable, as in the glow-
worm, it is very smooth. It receives the chyle from
the stomach.
The small gut (4) is usually strait, smooth, and of
equal size through its whole length, though there are
bulgings in some species ; and, for the most part, it
has many convolutions. The chyle, in passing along,
has its nutritive portions taken up by the inner mem-
brane of this intestine, through which it passes into
the cavity of the abdomen, and not, as in other
animals, into lacteals, in order to be converted into
red blood, which is not found in insects.
The blind gut (5) consists usually of an egg-shaped
cavity, formed by the bulging out of the lower end
of the small intestine. It is often covered with plaits
orbands ; sometimes the bile vessels open into it,
and it always contains the crude parts of the chyle
rejected by the small gut as unfit for nourishment.
(1) In Latin, Pylorus. (2) In Latin, Intestina.
(3) In Latin, Duodenum. (4) In Latin, Inestinum tenue.
(5) In Latin Caecum.
ORGANS OF DIGESTION. 65
Insects have no gut precisely similar to the colon of
other animals.
The vent gut(!) is very muscular, and usually short.
It ends in the vent(2), through which the crude parts (3)
of the chyle, collected in the blind gut, are thrown
out of the body.
The singular discharges of offensive matter, such
as the poison of the bee, and the vapour of the bom-
bardier beetle, are prepared near the vent gut by a
particular apparatus, and stored up in a sort of blad-
der, from which they are discharged.
In the abdomen of a certain class of bees in the
common hive, called wax workers, are cells between
the rings, in which wax appears to be prepared by
secretion from the food within, and not collected, as
is supposed, directly from flowers ; as the pollen is
well known to be upon the thighs for the purposes of
food. This opinion, however, which I have not myself
verified by observation, is contrary to that popularly
held. It was first started by Hornbostel, a clergyman
at Hamburgh, in 1744, and republished as his own
discovery, by Reim, in 1769. Mr. John Hunter, evi-
dently without being aware of these, published it as
his own discovery in 1792; and Huber, assisted by
the clever daughter of Professor Jurine, made experi-
ments and dissections, all confirmatory of the same
view. Resently G. R. Treviranus, one of the best
living experimental physiologists, has repeated the
investigations, and has come to the same conclusion.
I think these high authorities must outweigh that of
Mr. Huish, who decides that they are all wrong, and
that the popular notion is right.
The nutritive part of the chyle, which is (if the
term may be used) filtered through the sides of the
small gut, is not then received into any vessel, as has
(1) In Latin, Rectum. (2) In Latin, Anus.
(3) In Latin, Excrementa, or, Faces.
E
66 INTERNAL ORGANS.
already been said, but spreads about through the
interior of the body, taking the form of an irregular
mass of soft pulpy fat, greenish or whitish in colour,
which surrounds the organs of digestion, and fills up
every vacant place in the body, particularly in cater-
pillars, of which it forms a very large proportion of
the whole bulk.
The more fluid portions appear to be taken up
through the membranes of the several organs, pro-
bably in a similar way to that by which they pre-
viously passed through the membranes of the small
intestine. On this subject, however, we are still very
much in the dark: though it is certain the fat is em-
ployed for the purposes of nutrition ; for it is always
stored up in great quantity before an insect passes
into the state of chrysalis, when it ceases to eat, and
often remains torpid for many months ; and is also
found similarly stored up in the female before the
eggs are laid, but after this disappears.
The nutritive matter, whether it be fat or fluid, not
being carried through the body in arteries and veins
as the blood is in other animals, to nourish the several
parts, lies around and upon the parts to be nourished,
which absorb the peculiar portions they require, re-
jecting the rest ; and this may be required by other
parts for a different purpose.
The more solid portions may be required by the
muscles, the layers of the intestines, the horny skin,
and perhaps by the nerves; while the more fluid por-
tion may be taken up by the gastric vessels, the bile
vessels, and the peculiar vessel, which is the only
organ found in insects in the least resembling a heart.
ORGANS OF CIRCULATION.
THE organ or vessel in question was called a heart
by Malpighi and Swammerdam, and the older natu-
ralists ; but though it is now commonly called the
ORGANS OF CIRCULATION. 67
dorsal vessel (l) by modern writers, I shall use the
term heart, which, besides being again introduced by
Meckel, Herold, and Straus, is less repulsive to a
beginner ; and I shall endeavour to describe is so as
to prevent misconception.
The chief resemblance which the heart in insects
bears to that of other animals, is its containing a
fluid, and its regular beating, as may readily be
observed in smooth caterpillars, in which it is of large
size. Lyonnet counted twenty to one hundred beats
in the minute in the goat caterpillar, caused, it has
been said, by the alternate contraction of a number
of muscles ranged along its sides. It differs most
essentially from the heart in other animals, in having
no visible inlet or outlet in the form of veins or arte-
ries. Consequently, there is not, and cannot be, any
real or direct circulation of blood in insects, though a
claim to the discovery of such a circulation has been
lately made, upon very slight and vague grounds,
by Professor Carus, of Dresden, and too hastily
admitted by Mr. Spence, though the claim is not new,
having been made by Compare tti, on the faith of
minute dissections.
The heart lies along the whole extent of the back,
from the head to the vent, immediately under the
skin and muscles. It is in form of a cylinder con-
tracted at the two ends, but usually narrower towards
the head, and wider towards the vent.
It is composed of two membranes ; an outer of cel-
lular texture interlaced with numerous airpipes(2), and
an inner of muscular texture.
Within it is filled with a fluid, transparent, eoagu-
lable, readily drying, and, when dry, having the look
of gum, its colour being sometimes strong and some-
times greenish, orange yellow, or dull brown. Without,
(1) Latin, Vesicula dorsalis. (2) In Latin, Tracheae.
E 2
68 INTERNAL ORGANS.
the masses of fatty matter which sometimes surround
it in considerable quantity, are of the same tint as the
fluid within, and it may be, the fluid derives its co-
lour from them, though M. Audouin seems to think
the reverse is the case.
Meckel and Herold, considering the organ a
heart, think that its beatings, or alternate contraction
and dilatation, which affect its whole extent, are for
the purpose of agitating, not of circulating, the fluid
it contains, as they admit no outlet or inlet by means
of vessels for that purpose. Herold thinks that the
dilatation, or diastole, is produced by the triangular
muscles which attach it to the back ; while the con-
traction, or systole, is produced by the muscular fibres
of the inner membrane.
The heart of a carnivorous grasshopper, with its valves, cham-
bers, and artery, from M. Audouin.
"The dorsal vessel," says M Straus-Durckheim, a
naturalist of high talent, " is in reality the heart of
insects, being in them, as in higher animals, the mover
of the blood, which in them, instead of being con-
tained in blood vessels, is diffused through the cavity
of the body. The heart occupies the whole of the back
of the abdomen, and ends at the fore part of the organ
in a single artery(1) without branches,which carries the
blood into the head where it is poured out, whence it
flows back into the abdomen, in consequence solely of
its accumulation in the head, in order to enter anew into
(1) This was anticipated in part by Lyonnet, page 412.
ORGANS OF CIRCULATION. 69
the heart. To this alone is reduced the whole circu-
lation in insects, which accordingly have but one
artery without branches, and no veins.
" The wings of the heart are not muscular, as
Herold pretends ; they are simple fibrous ligaments
for retaining the heart in its place.
" The heart is divided within into eight successive
chambers, in the cockchafer, separated from each
other by converging valves, which allow the blood to
pass forwards from one to another as far as the artery
that conducts it into the head, but oppose its move-
ment backwards. Each chamber is furnished at its
fore part on the sides with two openings in form of cross
chinks, which communicate with the cavity of the
abdomen, and through these the blood contained in
the latter can enter into the heart. Each of these
openings has within it a little valve, in the form of a
half circle, which shuts up the passage during every
contraction.
" From this brief detail, it may be conceived, that
when the chamber nearest the vent is dilated, the
blood in the cavity of the abdomen will enter through
the two openings (l) above described. When this
chamber contracts, the blood which it contains, not
being able to return into the cavity of the abdomen,
shuts the valve(2), and passes into the second chamber.
This dilates for the reception of the blood, and at the
same time it receives a certain quantity of blood by
its proper openings. Then, by the contraction of this
second chamber, the blood passes in the same manner
into the third, which receives it equally by the side
openings. In this way the blood is propelled from
one chamber to another, till it reaches the artery ;
and it is the successive contractions of the several
(1) In Latin, Auriculo-ventricularia.
(2).In Latin, Valvula intcrventricularia.
70 INTERNAL ORGANS.
chambers of the heart which are observable through
the skin in the backs of caterpillars."
/A Ji Ml JI II uk
The heart of the cockchafer, with its valves, chambers, and
artery, from M. Straus Durckheim.
This is both very rational, intelligible, and supported
by minute and careful observation. It at once de-
stroys numerous fancies on the subject, proposed by
Cuvier and Marcel de Serres.
The blood then appears to be partly prepared by
transmission through the coats of the intestine, and
again probably undergoes changes in its passage to,
and its course through, the heart; and being diffused
through the cavity of the body without being confined
in blood vessels, it is probably distributed whither it is
wanted by the muscular movements of the animal,
and assimilated by what is termed imbibition.
Organs of Breathing.
Ih the larger animals, the blood, by means of lungs,
is exposed to fresh air, taken in by the mouth and
nostrils, and through the windpipe passing into the
lungs, where it gives off oxygen to the blood, and car-
ries off carbonic matter from the blood. In insects
there are no lungs, and consequently no air is taken
in by the mouth (there are no nostrils) by breathing.
ORGANS OF BREATHING. 71
Fresh air, however, is as essential to insects as to
other animals, though it enters their bodies in a dif-
ferent manner ; since, instead of one, two, or three
opening's for breathing, there are usually eighteen,
generally very obvious in the larger caterpillars ; their
function being demonstrable by stopping them up
with oil or grease, when the animal is soon suffocated
and dies.
These openings are termed spiracles (!), and are of
two sorts, simple and composite.
A spiracle magnified to show the lips open to inhale the air in
breathing.
The simple spiracles (2) are usually situated on the
sides of the abdomen, a pair (one on the right and
one on the left) to each ring, at the junction between
the back arch and the belly arch. Like the nostrils
in man and other animals, these spiracles are often
beset with hairs, crossing and meeting, for the purpose
of preventing the entrance of what might prove inju-
rious, while the air may pass pure.
The position assigned them, as well as their number,
varies considerably, to suit the habits of the insect.
In the maggots of some flies, for instance, which feed
on greasy substances, or live in water, there is only
one spiracle at the end of the last ring which can be
stretched out like a telescope into the air, while the
body is enveloped.
The second and third rings of the body of caterpil-
lars answering to the mid and hind corselet, having
no spiracles in caterpillars, and the exact parts where
(1) In Latin, Spiracula, improperly Stigmata.
(2) In Latin, Spiracula simplicia.
72 INTERNAL ORGANS.
they might be looked for being the place where the
four wings are afterwards jointed, M. Blainville infer*
red that the wings, when expanded, in the moth and
butterfly, were nothing more than spiracles. In this
singular opinion, M. Audouin would have agreed,
had it not occurred to him, that if the wings were to
be considered spiracles, there would not be both wings
and spiracles in the same insect at these four points,
which upon examination he actually found, as in the
cockroach and the mole cricket; and of course M.
Blainville's fancy is thence annihilated.
The opening of these spiracles is surrounded by a
ring, more or less circular, and somewhat elevated,
which being contractile, may be considered as similar
to the lips of the mouth.
The composite spiracles (l) are never placed in the
abdomen, but exclusively in the fore corselet, and are
(so far as is at present known) only two in number.
These are very obvious in grasshoppers. They are
composed of two horny pieces, which move outwards
and inwards in the process of breathing, like a pair of
folding doors, their movements being produced by two
muscles.
The spiracles convey the air which they inspire
from without to a corresponding number of air pipes,
to be carried into the body, as the air inspired by
man is carried into the windpipe and the lungs. The
several air pipes which go from the spiracles end in a
common pipe on each side, and these two common
pipes may be termed the main air pipes (2). They run
lengthways from the head towards the vent, and send
off innumerable small branches to convey the air to
the different parts of the body, somewhat like the
branches of certain shrubs ; the'branchlets (3) interlace
(1) In Latin, Tremaeree or Spiracula composita.
(2) In Latin, Tracheae. (3) In Latin, Ramuli*
ORGANS OF BREATHING. 73
the membranes, penetrate the muscles, and extend
through the legs and the wings.
Two sorts of these air organs have been distin-
guished, the one tubular or pipe-like, as those we have
just described, and another vesicular or cell-like.
The first sort, or air pipes (*), are composed of three
distinct membranes, the outer and inner of which are
thick, extensible, and of a cellular texture, while the
middle one is formed of a gristly thread rolled spirally
round in the manner of a corkscrew, and very similar
to the spiral air pipes of plants. This gristly spiral
thread is very elastic, in consequence of which the
pipe is kept uniformly open, for even when it is com-
pressed by the muscles, it immediately expands again.
There is a similar mechanism of gristle in the human
wind pipe.
These air pipes have also been distinguished, from
their situations, into arterial and pulmonary, the arte-
rial being those which come directly from the spira-
cles ; and the pulmonary, the two large pipes on each
side of the body, (not always traceable), from which
other arterial pipes branch off. The structure of both
these is similar.
The second sort, or air-cells (2), are without the
spiral gristle, being composed only of an outer and
inner membrane. Consequently, those air cells, when
not filled with air, must become flaccid by their sides
collapsing. They are not in the form of pipes, but
like cells or pouches, mutually communicating with
each other through very short and simple canals.
They never commnnicate directly with the spiracles,
but receive their air from the air tubes. They are not
found in all insects ; but, when they occur, they appear
to serve the purpose of reservoirs for air.
They vary also in number and in size. In the rose
(1) In Latin, Tracheae tubulariee.
(2) In Latin, Tracheae vesicularia.
74 INTERNAL ORGANS.
chafer, for example, they are very small and very
numerous; but comparatively large in grasshoppers
and crickets. In these insects, the air cells can be
easily counted. It would be a difficult matter to in-
flate them with air, had there not been an ingenious
contrivance to facilitate this, in a sort of ribs with
which their sides are provided, discovered by Marcel
de Serres, and consisting of small projections from the
edge of each ring of the belly, and not distinct jointed
members.
The breathing apparatus in the Praying Mantis, showing the
numerous air tubes and air cells on each side.
ORGANS OF SENSATION. 75
The air then is breathed by means of these various
organs, and acts on the blood, or the fluid similar to
blood, somewhat, it may be presumed, in the same way
as it acts on the human blood, in the lungs, oxygen
being abstracted, and carbonaceous matter carried
off(').
The insects which live under water constantly or
partially, have peculiar organs for decomposing the
water or the air it contains in order to procure oxygen,
which appears to be indispensable to life. Some of
these water insects, indeed, come ever and anon to the
surface, in the same manner as the water eft and the
whale, to breathe the air. Others remain always un-
der water.
ORGANS OF SENSATION.
IT is well known that in man, the brain and spinal
cord, with the nerves proceeding from them or con-
nected with them, are the organs of feeling or sensa-
sation, the brain being encased in the strong bones of
the scull, and the spinal cord in the no less strong
and peculiarly-jointed bones of the back. The nerves
in insects differ much from those of man, and particu-
larly in there being no peculiar structure like the
skull, and the bones of the spine, to encase what may
be termed the main stem, whether that be considered
the origin or the receiver of the branches. This main
stem in insects, however, which lies along the breast
and belly, from the head to the vent, is protected by
the inner breast-plate from being compressed by the
gullet, as has been already noticed.
In man, the brain is distinguished into two parts,
the spinal cord being a third ; but besides these there
is a system of numerous and extensive nerves, which
(1) This will be fully explained in the "ALPHABET OP PHYSI!
OLOGY."
76 INTERNAL ORGANS.
is only connected with the three parts just mentioned
by very small twigs, and is therefore considered as
being partly independent of them. This partially in-
dependent system of nerves in man is termed the gang-
lionic system, and it is sometimes also called the great
sympathetic nerve, or the intercostal nerve.
Now it is generally maintained by naturalists, that
insects possess only this ganglionic system of nerves,
and have no brain or spinal cord like that of the
larger animals.
It may be well, before proceeding farther, to describe
a ganglion, which is a knot or mass of nervous sub-
stance, at a point where two or more nerves meet, and
appears to consist of two substances similar to
those of the brain, while it differs from a nerve in
being firmer in texture, redder in colour from a greater
supply of blood, and covered with a membrane of
closer texture. The fibres or threads of the nerves
which join such a nerve-knot or ganglion, become
twisted within it, as Scarpa says, into a bundle,
and threads from the several joined nerves unite to
form a new nerve, which is always larger than any of
those whence it has been formed. This constitutes a
ganglion in man.
Instead of a brain, then, insects have generally in
the head a double nerve-knot or ganglion, contained
in a horny cavity larger than itself. This, for the
sake of distinction, may be called the ganglionic
brain (*) ; inasmuch as it differs from the ganglionic
system in man by sending nerves to the eyes, the ears,
and the mouth, while the former appears (so far as is
yet understood) to supply nerves only to the heart,
stomach, intestines, and other organs, whose motions
are involuntary. The ganglionic brain also differs
from the brain in man by being surrounded with
(l) In Latin, Cerebrum ganglionicum.
ORGANS OF SENSATION. 77
powerful muscles which move different portions of it,
whereas, there are no muscles to move the human
brain. Besides the nerves to the eyes, the ears, the
mouth, from the fore part of the ganglionic brain in
insects, and two nervous films behind, difficult to
detect, and probably running to the heart, — two thick
nerves go off from the base, and after forming by
their separation a sort of ring or collar, which, dipping
down, embraces the gullet, they re-unite at what may
be called the second nerve-knot or ganglion (l), below
the gullet, whereas the brain is above the gullet.
In the same way, two nerves go off from the lower
partof this second nerve-knot or ganglion, and re-unite
at a third (2).
Two nerves go off from the third in a similar way,
and thus, at intervals, a chain of nerve-knots or gan-
glia, united by double nervous cords, is formed along
the belly of the insect to the vent.
The number of nerve-knots or ganglia varies in
different species. Sometimes there is one for each
ring of the body, and in other cases, not so many as
this. The louse has only three, while the mole-cricket
has nine, and the green field cricket has ten.
When one of these nerve-knots is carefully observed,
it is found to be usually spherical or pear shaped,
sometimes flat, (in the gipsy-moth, the third is heart-
shaped) consisting, like the ganglionic brain, of two
lobes, not always of the same form, even in the same
insect.
Besides the two main nerves, or double nervous
chord which unites the several nerve-knots into a chain,
there goes off from each, on both sides, small nervous
branches, and these again divide into branchlets
smaller and smaller, which are distributed to the gullet,
(1) In Latin, Ganglion secundum.
(2) In Latin, Ganglion tertium.
78
INTERNAL ORGANS.
the stomach, the air-pipes, and the muscles throughout
the body.
Lyonnet counted forty-five pairs of these nerves,
and two single ones in the goat caterpillar, making
in all ninety-two, which is fourteen more than are
found in man.
The double nervous chords uniting the ganglia are
tubular, and composed of two substances, the mem-
brane forming the tube, and a sort of marrowy sub-
stance with which this is filled. It is probable, that
the smaller branches are similar in structure.
The nervous system in a garden beetle (Carabus}. a, the first
nerve-knot or ganglion, with a large nerve on each side going
off to the eyes ; b, the second nerve-knot ; c, the third, nerve-
knot 5 d, e, /, g, h, the other nerve-knots or ganglia,
ORGANS OF SENSATION. 79
It is not improbable that each nerve-knot may form
the centre of feeling to the parts with which its nerves
communicate ; and if this be so, it will afford some
explanation of the fact, which is no less singular than
it is ascertained beyond question, that insects obvi-
ously do not feel so much pain from wounds and in-
juries as larger animals. Hence it appears to be,
that the abdomen of a wasp or a bee will continue to
live, and thrust out the sting, long after it is severed
from the body ; and the head of a dragon-fly will eat
as voraciously after it is cut off, as if it had to supply
an insatiable stomach. The circumstances seem to
disprove, in the most decided manner, the humane,
though mistaken, opinion of the poet, so often quoted,
that
" The poor beetle which we tread upon
In corporal sufferance feels a pang as great
As when a giant dies."
No giant could kick if his body was cut asunder,
yet the bee stings in such circumstances ; no giant
could eat voraciously like the dragon-fly when his
head is cut off, nor walk about without his head, as a
common fly will readily do ; nor after his bowels have
been scooped out, as cockchafers often do.
May it not be that Providence has endowed insects
with less acute feelings, in order to lessen their suffer-
ings when preyed upon by birds and other animals,
for whose food they appear to be mainly intended ?
I throw this out as a plausible conjecture.
I have already briefly described the external ap-
pearance of the eyes, and what seem to be the ears ;
but it may be useful here to advert again to these and
the other organs of the senses.
The sense of Touch has been by many supposed to
reside in the organs I have ventured to call the ears,
which have thence been termed feelers, but the evi-
dence on which this rests is slight and unsatisfactory ;
80 INTERNAL ORGANS.
for the bending the ears forward, and moving them
in walking, seem to be for the purpose of listening.
I think that the numerous joints in the foot permit-
ting it to bend round objects, and more particularly
the soft-cushioned feet of some beetles and flies, and
also the feelers on the under jaws, and the under lip,
may be more plausibly considered the organs of touch ;
\vhile the hairs, and long bristles, and spines, of some
caterpillars, are evidently connected with the sense of
touch.
There can be no doubt that insects possess the
sense of Taste, several species being most delicately
fastidious respecting their food ; rejecting some leaves
and choosing others, when no difference is percep-
tible to us. It is not well ascertained in what part of
an insect's mouth the organs of taste are situated,
though I think it more plausible to consider the
tongue as such than the feelers, or the haus, as has
been done by some authors.
Most insects possess an exquisite sense of Smell,
but as they do not breathe through nostrils and do not
possess them, we are naturally led to suppose the
organ of smell to be in the spiracles, — most probably
in the pair of spiracles on the fore corselet, which are,
it may be recollected, of different structure from the
other spiracles ; or, if M. Huber be correct, in a small
spiracle at the root of the tongue. Dumeril appears
to think that the whole lining of the air-pipes through-
out the body is the organ of smell — evidently a gra-
tuitous assumption highly improbable.
For the brief reasons assigned under touch, and
for others deduced from dissection and experiment,
I have ventured to call the Ears, two horn-like organs,
always situated near the eyes, to which various incon-
gruous functions have been assigned. As I have little
doubt these organs will one day be proved to be ears,
I think it will direct attention more decidedly to them
by at once terming them ears, than by leaving them
ORGANS OF SENSATION. 81
open to all sorts of crude fancies, so easy to form, but
so detrimental to correct inquiry.
The Vision of insects is much better understood
than that of the other senses. As I have already
described the simple and compound eyes of insects,
so far as their outward structure is concerned, I shall
now call attention to the nerves of the eyes. (*)
In insects which have large eyes, these nerves are
exceedingly large, bulging out after they go off from
the ganglionic brain into considerable knobs. In the
stag-beetle, in which these are pear-shaped, so many
minute branchlets go off to the eye, (one probably to
each facette,) that it is not possible to count them.
In the hive bee the knobs of these nerves are kidney-
shaped, and so much larger than the brain itself, that
they might lead an indifferent observer to suppose
they were actually the brain.
The head nerves in the bee. a, the first nerve knot or gang-
lion, with its forked division below ; b, the small nerves of the
head ; c, c, the two large nerves of the eyes.
It is remarkable that the eyes of insects are supplied
with large air pipes, arising from the main air pipe in
the head ; one rather large, surrounding the eye, and
many others going off from this and dividing into
(1) In Latin, Nervi optici.
F
82 INTERNAL ORGANS.
equal angled triangles, as has been minutely described
by Marcel de Serres.
I have proved by experiment that M. Latreille was
mistaken in supposing a small black ant, common in
France, to be blind : I found it on the contrary very
impatient of light.
ORGANS OF REPRODUCTION.
UNLIKE snails and worms, among which there is no
distinction between the males and females, insects
have the two sexes as distinct as the larger animals,
and in many respects are similar to birds, so far as
pairing is concerned, — that is, a single male associates
with a single female. Exceptions to this general rule
occur among hive bees, and the white ants of warm
countries ; a single female, called the queen, being
attended by many males, while the young are nursed
by a peculiar class, (not exactly females, but more
like these than like males,) called nursers, or workers.
The reverse takes place among poultry and black
cattle, one male being attended by many females.
Among ants, wasps, and humble bees, several indi-
vidual females in the same hive are attended by
several males.
Insects differ from birds and many other animals,
in the male taking no share whatever in providing
for the young, either before or after pairing.
The male is generally smaller than the female,
sometimes, but not always, brighter or differently
coloured ; is distinguished in moths and gnats by the
ears being feathered or ornamented, while those of the
female are plain; and in grasshoppers and cuckoo-flies
by wanting the ovipositor. In some insects the male
ORGANS OF REPRODUCTION. 83
has ample wings, when the female has none, or very
minute ones, not adapted for flying.
The Vapourer moth, the female with plain ears and with very
short wings ; the male with feathered ears and large wings.
The male insects are, in most cases, more restless
and wandering than the females, and of course more
frequently seen, differing in this from spiders, the
males of which are seldom or rarely seen.
All female insects have eggs, which, in a few cases,
are hatched within the body, but are generally laid in
such places as the young may readily find food when
hatched; the mother, in most instances, dying soon
after the laying, and of course the young have from
the first to shift for themselves.
These are ascertained facts which cannot be ques-
tioned, though they do not accord with the popular
error of insects being generated by putrefaction, and
by blighting fogs or winds, much less the so-called
philosophical theory of their being generated by some
sort of mysterious chemistry.
This theory was supposed to be unanswerably sup-
ported by the multiplication of microscopic animal-
cules in water, which could not, on account of their
minuteness, be traced to their parents. This, however,
though apparently impossible, has recently been done
by Professor Ehrenberg of Berlin, who, by putting
the animalcules in coloured fluids, succeeded not only
in discovering their eggs and the hatching of these
F2
84
INTERNAL ORGANS.
but in tracing them before they were laid in the egg-
organ of the mother (1).
M. Ehrenberg was no doubt assisted in this by the
circumstance, which generally holds good, of the eggs
of insects and small animals, being proportionably
much larger, compared with the mother, than in birds.
From this circumstance, the eggs of insects may,
in many cases, with a little care, be traced in the
egg-organ of the mother, as has been done by M.
Straus-Durckheim in the cockchafer, and by Swam-
merdam in a much smaller insect — the louse.
Egg organ in the louse magnified; a, the right branch con-
verging; b, the left branch diverging ; c, an egg in the egg tube
ready to be excluded; d, d, the fountain which furnishes the
glue.
Male reproductive organs in the blister beetle.
(l) in Latin, Ovarium.
ORGANS OF REPRODUCTION. 85
When an egg is laid by an insect, it is, except in
a very few cases, glued to the place where it is laid
by a sticky fluid provided for that purpose, and dis-
charged along with the egg, or immediately after it ;
the vessel producing which fluid in the louse may
be seen in the figure. The louse glues its eggs to hairs";
moths and butterflies glue theirs on the bark or leaves
of plants and trees, where they usually remain
through the winter, to be hatched the following
spring.
It is thence obvious that the eggs of insects, thus
firmly glued, cannot, as has been fancied by the un-
learned, as well as by philosophers, float about in the
air, than which, indeed, they are always much heavier.
Several species of insects, instead of gluing their
eggs in this manner, place them in nests, as is done
by the bees and wasps, appropriately called miners,
masons, carpenters, or upholsterers, according to
the processes they pursue in building their nests.
Other species dig holes in the ground, or cut out
grooves in wood, in which to lay their eggs, and are
provided with curiously-constructed instruments for
that purpose, such as the grasshopper, whose digging
instrument is like a scymitar; the saw-flies, whose
instrument is like a double saw ; and the gall-flies,
whose instrument is like an awl.
Instruments for depositing eggs ; a, that of a cuckoo fly ;
b, that of a grasshopper } c, that of a saw fly.
86 INTERNAL ORGANS.
Several species, well termed cuckoo-flies, thrust their
eggs into the nests or the bodies of other insects, or
animals, and have appropriate boring instruments for
this purpose.
This is indeed one of the most singular circum-
stances in the economy of insects, and frequently leads
to no little disappointment, when collectors feed cater-
pillars for the purpose of breeding moths from them ;
for instead of the expected moth, a brood of cuckoo-
flies, whose maggots had been feasting on the body of
the caterpillar, make their appearance, and immedi-
ately pair and set out upon excursions for the disco-
very of other caterpillars, into which they may thrust
their eggs.
EGGS OF INSECTS. 87
GROWTH OF INSECTS.
I HAVE here selected the word " growth" in prefer-
ence to development, both because it is shorter, more
English-like, and less startling to beginners, and be-
cause development has recently become one of the
catch words of an absurd theory, and has been twisted
from its true meaning, by applying it comparatively
to two or more animals, instead of confining it, as it
always should be, to an individual. Metamorphosis is
still more objectionable, where similarly applied, and
I have elsewhere used " Transformations," as some-
what less so.
EGGS OF INSECTS.
INSECTS' eggs are not all of an oval form like those of
birds, but some are like a pear, some like an orange,
some like a pyramid, and some like a flask.
Various shaped eggs of insects magnified.
The eggs of the gnat, for instance, may be com-
pared, in shape, to that of a powder flask, and the
mother gnat lays about three hundred at a time. Now
each egg, by itself, would sink to the bottom of the
water; yet the gnat puts the whole three hundred
together in the form of a little boat, and in such a way,
GROWTH OF INSECTS.
that they will all swim on the surface of the water ; and
a very curious way she has of managing this.
Like other insects, the gnat has six legs. Four of
these (the four fore-legs) she fastens to a floating leaf,
or to the side of a bucket, if she is on the water con-
tained in one. Her body is thus held level with
the water, except the last ring of her abdomen,
which is a little raised. This being done, she begins
to make use of her other two legs, (or hind legs) and
crosses them in the shape of the letter X. The open
part of this X, next to her tail, serves as a kind of
scaffolding, to support the eggs she lays, until the boat
is formed. Eaca egg, when laid, is covered with a
kind of glue ; and the gnat holds the first laid egg in
the angle of the X until the second egg is laid by its
side, and glued to it ; she then glues another egg to its
other side. All these stick together thus ***, making
a kind of triangle, or figure of three, and this is the
beginning of the boat. Thus she goes on, piling egg
upon egg, always keeping the boat in proper shape by
her useful hind-legs. As the boat grows in size she
pushes it from her by degrees, still adding to the un-
finished end next to her body. When the boat is half-
built, her hind-legs are stretched out thus =, the X or
cross form is no longer wanted, and she holds up the
boat as cleverly as if it was done with two out-stretched
arms.
The boat is at length completed, and an excellent
boat it is, quite water tight. For though it is very
small and delicate, yet no tossing of the waves will
sink it ; and nothing can fill it with water, or turn it
upside down. In fact, the glue with which it is
covered prevents it from ever being wet. Even if the
boat be pushed down to the bottom of the water, up it
comes again quite dry : so that it is better than the
best life-boat that has ever yet been invented (l).
(1) Working Man's Companion, Cottage Evenings, p. 54.
EGGS OF INSECTS.
The eggs of insects are not, like those of birds,
always smooth ; but are sometimes ribbed, and some-
times tiled, or otherwise sculptured or carved on the
outside.
The shell of an insect's egg is rarely or ever brittle
like that of a bird, but composed of a tough membrane
which, in some instances, can be stretched out, as ap-
pears from the eggs of ants and some other insects
growing considerably larger in the process of hatching.
The mother insects, usually dying before their eggs
are hatched, do not sit upon them like birds, except in
the singular instance of the earwig, which, from the
proceedings of one kept by me in a glass, in March,
1832, appears to attend more to shifting the eggs
about to places where they may receive moisture, than
any thing like hatching by covering them. Ants shift
their eggs according to the changes of the day and
night, and also of the weather, placing them near the
surface of their nests when it is warm and dry, and
deep down when it is cold or wet.
In consequence of being exposed to the same tem-
perature, all the eggs of any particular species, in any
given district, are hatched exactly at the same time,
or at most within a few days ; and when such eggs
are numerous, an immense number of caterpillars
make their appearance all at once on plants and
bushes, and give rise to the notion that they are
brought by winds, or generated by what is called
blighting weather, though this is as absurd as to say
the wind could bring a flock of cattle, or that the
blight could generate a flight of sparrows or rooks
without eggs to hatch them from.
By looking carefully on the bark of rose or currant
bushes, or on the back ribs of gooseberry leaves, the
eggs may be found sometimes in patches, sometimes
in rows, whence the caterpillars are hatched that creep
into the buds, or stream over the leaves and devour
them.
90 GROWTH OF INSECTS.
INFANCY OF INSECTS.
THERE is no single English word which will apply
$o every insect just after it is hatched, and while it
temains in what may be called its state of infancy ;
J)ut there are several English words which apply to
this state in different sorts of insects, as I shall now
explain.
Insects in the infant state ; «, caterpillar of a saw fly ; 6, grub
of a ladybird ; c, maggot of a cheese fly magnified.
The word " CATERPILLAR " (*) is applied to the
creatures which are, with a few exceptions, shaped
like an earth-worm, and of various colours, but most
commonly green, sometimes smooth, sometimes stud-
ded with short or with long hair, and sometimes with
a sort of thorns, and having exactly six legs always
placed on the corselet and furnished with claws,
while they have from two to sixteen clinging feet (2)
without claws, always situated on the rings of the ab-
domen. All caterpillars are hatched either from the
eggs of butterflies, moths, or saw flies, with four
wings, and, when full grown, they become butterflies,
moths, or saw flies, like their parents.
Among the caterpillars best known and most de-
structive are gooseberry and willow caterpillars, which
(1) In Latin, Eruca.
(2) In Latin, Prehensores, objectionably Propedes.
INFANCY OF INSECTS. 91
become saw flies, as does the small caterpillar, erro-
neously called the turnip fly (l). Other well known
caterpillars are the large caterpillars which feed on
cabbage, and become white butterflies, and small gre-
garious caterpillars which destroy hedges and fruit
trees, afterwards becoming moths, as do those which
roll up the leaves which they eat, or creep into buds,
constituting the well known " worm i' the bud.'5
Qther caterpillars, which become small moths, devour
grain in granaries, the wood of currant and willow or
other trees, garments of woollen or silk and furs, and
insects and other animals kept in cabinets.
The word " GRUB" is not quite so definite as cater-
pillar, and is often applied popularly, but erroneously,
to both caterpillars and maggots. In precise language,
a grub is a creature hatched from the egg of some
sort of beetle or weevil (which is a beetle with a long-
ish snout). A grub has always exactly six feet on the
corselet, and never any clinging feet on the abdomen
like caterpillars. The body of a grub is also, with a
few exceptions, more clumsy than that of a caterpillar,
the general colour being white, yellow, or brown,
never, ] believe, green ; and the head usually some
darker colour, as blackish or dark brown.
The best known grubs are those of the cockchafer,
which takes three years to arrive at its full growth,
and devours the roots of grass; those of the corn
weevil, which do great injury in granaries ; and those
of the weevils that feed on nuts, and on the buds of
apple and other fruit trees, as well as on the roots of
cabbages and turnips, producing knobs on them. The
meal-worm and the wire-worm are also grubs, as well
as those which worm-hole furniture, gnaw bacon, and
destroy the bark of trees. One of the pests, called the
turnip fly, is the grub of a weevil. All these become
(l) There is a beetle grub also called the turnip fly.
92 GROWTH OF INSECTS.
beetles in their adult state, which in turn produce
a fresh laying of eggs from which other grubs are
hatched.
The term " MAGGOT" is more precise than grub,
though some maggots are erroneously called grubs.
Maggots are never produced from the eggs of butter-
flies, moths, saw flies, beetles, or weevils, but always
from the eggs of two-winged flies, or from bees or
wasps. A maggot differs from a caterpillar or a grub
in having no feet, and from an earthworm in never
being of a dull red or dingy green colour, but usually
white, greyish, often transparent, so as to show the in-
testines, and, in the case of the water maggots, called
blood-worms, of a bright blood red.
The best known maggots are those of the blow-fly,
which live on meat, either fresh or putrid ; those of the
bot fly, producing the disorder called bots in horses ;
those of the cheese-fly, called jumpers, or hoppers,
and sometimes erroneously mites, (mites not being
insects at all, but ranking with spiders) ; and those of
the crane flies, which destroy grass and corn fields,
often improperly called the grub. The wheat fly, as it
is called, and the Hessian fly, which have proved so
destructive, are both grubs of small flies, not unlike
gnats.
Maggots are popularly called mawks in the North,
and gentles in the South, and very often worms.
These three sorts — caterpillars, grubs, and maggots
— are, by modern naturalists, called by a Latin word,
which means a mask or a phantom (*) because Linnreus
took a fancy to suppose them only insects in a mask,
which when they had thrown off", they were> of course,
unmasked. I think the term objectionable and im-
proper, though it is often convenient for want of a
better.
(1) This Latin word is Larva.
ADOLESCENCE OF INSECTS. 93
These infant insects, indeed, often throw off their
skins, or moult, as it may be termed, during their
growth, the old skin partly splitting and sloughing off ;
but this old skin is no more a mask than the feathers of
a bird, which are moulted once or twice a year, can be
called a mask.
Like most young animals, all caterpillars, grubs, and
maggots, eat voraciously, as it is necessary to supply
nutriment for their increasing growth.
ADOLESCENCE OF INSECTS.
Adolescent insects ; a, the peacock butterfly j 6, the blue-
bottle fly j c, the cockchafer ; d, the dragon-fly.
THE English word adolescence, though derived, like
infancy, from the Latin, is well understood as applied to
the period of life between infancy and full growth.
Except this, there is no term which occurs to me as
applicable to the stage of insects succeeding the one
just described. I have only adopted it here, however,
not because I think it good, but because I cannot find
one more suitable.
In this stage, insects differ more remarkably from
the larger animals than almost in any other particular ;
for while the latter remain active and continue, as
before, to eat and grow, the former in few instances do
neither, but remain in a very singular state of torpor.
94 GROWTH OF INSECTS.
Preparatory to going into this state, many insects
make a sort of nest, called cocoon (*), to lie in ; others
hang themselves up by the tail, by a very ingenious
process ; and some remain active and move about, as
in the case of bugs, locusts, grasshoppers, crickets, and
dragon-flies.
Besides the insects which make a cocoon, many
of those which do not, upon moulting their last
skin in the caterpillar, grub, or maggot state, acquire
a covering, in some cases horny and tough, in
others thinner and more transparent. In this enve-
lope they remain, till the soft juices accumulated in
their previous state become duly assimilated to their
proper organs or members, and form the horny skin of
the body, together with the legs and wings.
In butterflies, such as the peacock and the
alderman, this covering appears shining, as if gilt,
and a Latin (2), and also a Greek (3) word, implying
gilding, was given to butterflies in this state, and
thence these words were extended to instances in
which there was no gilding, and the terms, from fre-
quent use, may now be considered half naturalized as
English words, particularly the term chrysalis.
Those with gilt coverings, as is the case with most
butterflies, are in this state of alongish form, with seve-
ral projecting corners and angles, with no appearance
of feet or wings. Moths, again, in this state, are usually
longish and tapering, with distinct rings and spiracles
for breathing along the sides. Two-winged flies are
in form of an egg, except being equal in thickness
at each end. Most beetles and gall-flies have no case-
covering, but remain with their legs folded closely
over their breast. It has been already mentioned
that bugs, crickets, grasshoppers, and dragon flies are
(1) In Latin, Incunabulum.
(2) The Latin word is Aurelia.
(3) The Greek word is Chrysalis.
ADULT STAGE OF LIFE. 95
not thus laid up in case coverings, nor do they rest
with their legs folded, but walk actively about.
Insects, when laid up in these case coverings, were
fancied by Linnaeus to resemble infants bewrapt in
swaddling bands, once common all over Europe, and
a Latin word (*), indicating this, was thence applied ;
and to those not laid up, but remaining active, the
fanciful term, nymph. The latter is objectionable,
because it can only be applied to female insects, while-
it has been indiscriminately used for both male and
female. The former, though almost naturalized in
English, is liable to the same objection, and ought,
therefore, to be in the neuter gender. So far as this
term means an infant, it is incorrect, but the Romans
used it "both for a baby, a doll, and a girl before ar-
riving at womanhood, and in this latter sense it may
be used, if no better term occur.
ADULT STAGE OF LIFE IN INSECTS.
IN the same vein with the fanciful resemblance of
a caterpillar to a masked insect, and of an adolescent
insect to an infant wrapt in swaddling bands, Linnaeus
fancied that the adult insect, now unmasked and un-
swaddlecl, resembled a picture, image, effigy, copy,
pattern, or representation of an insect, and thence
adopted a Latin word (2) implying this, which is still
used by modern writers, though evidently both far-
fetched and incorrect, as it plainly means, not the
insect itself, but a statue or spectre of it. The disci-
ples of Linnaeus, however, accustomed to the art of
inventing fanciful meanings for words, and of mysti-
fying the plainest facts, will, no doubt, maintain that
Imago does not mean an image, but the insect itself ;
in the same way as those of the modern schools will
(l) The Latin word is Pupa, better Pupum.
(2) The Latin word is Imago, whence our English word Image.
96 GROWTH OF INSECTS.
maintain that what they fancifully call types, are not
like any other known " types/' the moulds, models,
or dies struck for the purpose of forming figures, nor
are they figurative representations, but the very animals
themselves. It is thus that fancy and inaccuracy take
the place of facts, and do incalculable injury to
genuine knowledge.
I would have had less objection to adopt, as I have
elsewhere done, the term perfect , as applied to adult
insects, had it not been in recent times grossly abused
in theoretical comparisons of one animal with another,
— a beetle, for instance, being termed perfect, because
several pieces of its mouth are moveable ; and a gnat
or a butterfly imperfect, because the pieces of the
mouth are joined into the form of a sucking pipe.
The distinction of the two forms is certain and unde-
niable ; the terms employed are no less impious than
insulting to common sense.
After remaining in the adolescent stage for a due
length of time, in some instances only a week or two,
— very commonly for several months, particularly the
winter months, — the case covering, when there is one,
or, when there is none, the outer skin, is thrown off,
and the insect emerges in its adult or full grown state.
The Twenty-plumed Moth magnified*
ADULT STAGE OF LIFE. 97
For a few hours after its emergence, it is usually
somewhat moist, the wings being unexpanded, and, as
it were, crumpled up, and the body not so distinct in
its outline as it afterwards becomes. In some beetles
also, such as ladybirds, the colours are pale, and the
first pair of wings, which form the wing cases, are soft,
and of a pale uniform colour, without the spot after-
wards seen on them.
It is now that the air tubes distributed through the
body, and particularly through the wings, perform
the important office of inflation ; and if a main wing-
rib be then cut across near the root, the part of the
wing to which it goes ever after remains shrivelled.
Those who are little acquainted with insects, are
exceedingly apt to think they grow like other ani-
mals, and from this cause commit many mistakes, not
perhaps of great moment, but which it may be proper
to rectify by examples. The most common British
butterflies are those which are white, and all are
usually looked upon as of the same species, differing
in nothing, except, perhaps, in the size, the latter be-
ing erroneously ascribed to difference of age. But the
fact is, that there are a considerable number of species
of our white butterflies, and probably more varieties
even of these than have yet been ascertained or de-
scribed. It is certain indeed that butterflies do not,
like the larger animals, increase in size as they grow
older ; for every individual, from the moment it be-
comes a butterfly, continues invariably of the same
size until its death. Butterflies, indeed, seldom live
longer than a few days, or, at most, a few weeks, and
during this time they eat nothing except a sip of
honey : and since this is so, it would be absurd to
expect that they could increase in size. It must not
however, be understood from this, that the same species
will always measure or wTeigh precisely the same; for
though this will hold as a general rule, there are many
exceptions, arising from the accidents the caterpillar
98 GROWTH OF INSECTS.
may have suffered, from which an individual butterfly
originated. It is only during the caterpillar state
that the insect eats voraciously, and grows in propor-
tion ; and if it is, during this stage of its existence,
thrown upon short allowance, it cannot acquire the
standard magnitude, and the butterfly will be dwarfed
from the first. The same remarks with respect to
growth, apply to insects of every kind ; and the fact
cannot be better exemplified than in the uniformity
of the house-fly, among which scarcely an individual
in a thousand, will be found to differ a hair's breadth
in dimensions from its fellows. The smaller flies that
sometimes mingle with the common house-fly, are
those that come from the maggots in cheese.
Few insects, after arriving at the adult state, live
more than a few days, or at most a few weeks : some
live for a few months, but this is an exception to the
general rule.
SYSTEMATIC ARRANGEMENT. 99
SYSTEMATIC ARRANGEMENT OF INSECTS.
THE only use of a systematic arrangement of insects
or other natural productions, appears to me to be its
convenience of bringing things together in some
logical order, both to aid the memory in remembering,
and the judgment in comparing and deciding upon
agreements and differences. A system, in this point
of view, is similar to the frame work of a cabinet, into
the partitions of which many little facts may be stored
and dove-tailed, that would otherwise be scattered
through the memory at random at the great hazard of
being lost.
Such systems, however, since the time of Linnaeus,
who set the baneful example, have been considered
the sole end and aim of study, and are even prepos-
terously represented as a high branch of philosophy,
though, viewed in this light, they appear to me no
higher nor more important than the play pebbles^
which a child may be seen to amuse itself in classing
in rows or circles, according to size, form, or colour.
Nay, — viewed in the light of a philosophical study,
they are worse than triflhig, — they are decidedly
injurious, by leading to serious errors, such as that
of sucking insects, having "jaws totally useless, can
do no injury to the agriculturist," which has been
asserted and published within the last two years,
by a fanciful theorist, with the ravages of the hop-fly
and the bean dolphin staring him with flat contradic-
tion in the face.(J)
(1) The same theorist has since proposed to prove the doctrine
of the TRIXITY, by what he calls a Trinarian System of Animals.
100 SYSTEMS.
In Botany again, what is preposterously lauded as
the Natural system, is asserted to lead at once to a
knowledge of the qualities of a plant by merely as-
certaining what is called its natural order ; in the face
of the glaring facts of the wholesome potatoe with the
poisonous deadly night-shade, and tobacco, being
found in one of these so-called natural orders ; and
the wholesome bread-fruit tree, the fig, and the mul-
berry, with the most poisonous known vegetable, the
upas, in another of these natural orders. (*)
Confining ourselves to insects, all sorts of blunders
are committed by those who undertake to display
what they term the natural system. Moths, for ex-
ample, are said to be distinguished from butterflies
by flying only during the night, though there are
numerous examples of day-flying moths ; and even
groups are actually termed diurnal by the very theo-
rists, who set out by telling us they are nocturnal.
A nocturnal-diurnal moth, can only, I should think,
be imagined to be of pure Hibernian origin.
There is no system indeed without some such
striking error either of omission or commission, and
hence we must be contented to make the best we can
of their imperfections.
I am most particularly disposed to object to the
very fanciful and theoretical terms Kingdom, Tribe,
the like, not only as being founded on no
obvious ground, there being no proper king, chief, nor
head, in the divisions so termed, but actually in-
volving serious hypothetical errors, contradicted by
well-known facts'. The terms " Class," " Order,"
"Rank," "Group," "Species," "Variety," from
having some basis to go upon, are much less objec-
tionable ; though it is not always necessary to employ
(l)This will be more fully explained in the "ALPHABET OF
BOTANY," now in preparation.
SYSTEMATIC ARRANGEMENT. 101
any particular term — numbers being in most cases
more simple and less liable to mislead.
Rejecting then the more recent and partially
fashionable systems as hypothetical, that of Fabii-
cius as complex and unnecessarily difficult, and that
of Linnaeus as wanting the grand requisite of dis-
tinctness, I think I cannot propose a better than that
of the distinguished Swedish naturalist, Baron De
Geer, from whose magnificent work on insects, pe-
rused with avidity in my younger days, I derived that
taste for the study which increases with every coming
year. In giving an outline of this system, I shall use
the liberty of making a few slight alterations, which I
think will render it more easy in assisting beginners to
arrange the insects which they may collect, or may
wish to study.
102 SYSTEMS.
OUTLINE OF A SYSTEMATIC ARRANGEMENT OF INSECTS.
INSECTS.
Animals with exactly six feet, and three divisions
of the body, more or less distinct.
Divided into
A. Winged Insects. B. Wingless Insects.
A.— WINGED INSECTS.
Divided into
I. — Four Winged Insects, with Membranous
Wings ; II. Four Winged Insects, with the first pair
more or less thick or hard ; III. Two Winged Insects.
I. FOUR WINGED INSECTS,ALL THE WINGS MEMBRANOUS.
Divided into
1. Those with powdery wings and a spiral sucker.
Butterflies and Motkt(l)
2. Those with the wing-ribs hairy. Caddis Flies or
Water Flies.(*)
3. Those with unequal wings, the first and second
pair hooked 'together. Saw -Flies, Cuckoo -Flies,
Wasps, Bees, Ants, (male and female, the workers
having no wings) Ruby Tails, and Bee Parasites.^)
4. Those with the wing-ribs netted like lace. Scor-
pion Flies, Day Flies, Dragon Flies, White Ants.
Timber Lice, (some of which have no wings) Pearl
Flies, and Ant Flies. (*)
(!) In Latin, Lepidoptera (LINN^US).
(2) In Latin, Trichoptera, (LEACH).
(3) In Latin, Hymenoptera, (LINNAEUS).
(4) In Latin, Neuroptera, (LINNAEUS).
SYSTEMATIC ARRANGEMENT. 103
5. Those with a sucker bent under the breast.
Tree-hoppers, Lantern Flies, Frog-hoppers, Plant Lice
or Aphides, and Cochineal Insects or Cocci (*).
II. FOUR WINGED INSECTS WITH THE FIRST PAIR
MORE OR LESS THICK OR HARD.
Divided into
1 . Those with the first pair of wings leathery at the
base, and over-lapping the second pair cross-ways, and
having a sucker bent under the breast. Tree and Plant
Bugs (the bed bug has no wings) , Water Bugs, and
Water-measurers (2).
2. Those with the first pair of wings leathery through-
out, overlapping at the edges only, and covering the
second pair, which are folded lengthwise. Locusts,
Grasshoppers, Crickets, Mole-crickets, and Cock*
roaches (3).
3. Those with the first pair more or less horny,
forming cases, sometimes long, sometimes short, for
the second pair folded up when at rest beneath them.
Beetles, Chafers, Weevils, Earwigs (4).
III. TWO WINGED INSECTS.
Divided into
1 . Those with poisers in place of the second pair of
wings and a sucker. Gnats, Mosquitoes, Crane Flies,
Midges, Gadflies, Dung-flies, Bee-flies, and Common
House-flies (5).
2. Those with only two wings, in some cases none,
and longish jaws. Bird-flies, Bat-flies, Sheep-flies,
Forest-flies (6).
(1) In Latin, Homoptera, (LEACH).
(2) In Latin, Hemiptera, (LEACH).
(3) In Latin, Orthoptera, (OLIVIER).
(4) In Latin, Coleoptera, (ARISTOTLE).
(5) In Latin, Diptera, (ARISTOTLE.)
(6) In Latin, Homaloptera, (LEACH).
104 SYSTEMS.
B.— WINGLESS INSECTS.
[N.B. Bugs, timber-lice, ants, white ants, and
some female moths, do not rank in this division, though
they have no wings. We cannot make nature bend
to our systems.]
Divided into
1. Those with the hind legs formed for leaping.
Bed-fleas, Bird-fleas, Dog-fleas (').
. 2. Those with tail bristles formed for leaping.
Spring-tails (2).
3. Those with no members formed for leaping.
Head-lice, Body-lice, Crab-lice, Sheep-ticks, Dog-ticks,
^Bird-lice.
The drawers of a cabinet may be ticketted either
with the above letters and numbers, or with the Latin
names in the notes, and the insects collected may be
arranged accordingly.
In order to class and name individual species, there
is little aid at present, except through the medium of
very expensive books. This will be partly obviated
by my little ^ CONSPECTUS OF BRITISH BUTTERFLIES
AND MOTHS," and I hope soon to be able to get
through the rest of our British Insects in the same
way, progress having been already made with the
" CONSPECTUS OF Two WINGED FLIES," according to
Meigen, Fallen, and other high Continental authori-
ties ; and the " CONSPECTUS OF SPIDERS AND MITES,"
according to Lister, Clerck, and Walckenaer, which
will be accompanied by " THE ALPHABET OF SPIDERS
AND MITES."
(1) In Latin, Thysanura, (LEACH).
(2) In Latin, Anoplura, (LEACH).
INDEX.
ABDOMEN in Insects, 34, 57
Acetabulum, 48 note
Aculeus, 58 note
Adolescence of Insects, 93
Adult stage of life in Insects, 95
Adult Insects never increase in
size, 96
Air-cells, 72
Air-pipes, 72
Air-pipes of the eye, 81
Ala, 47 note
Alee anterioris, 50 note
Alee posterioris, 55 note
Alulae, 55 note
Antefurca, 26 note
Antennae, 34 note and 37 note
Anus, 65 note
Anoplura, 104 note
Apex anterior, 53 note
Apex inferior, 53 note
Apodemae articulationis, 52 note
Apodemee insertionis, 32 note
Appendage, objection to the term,
37
Arches of the back and of the
belly, 34
Arcus, 34 note
Arcus tergi, 34 note
Arcus ventris, 34 note
Areee, 52 note
Area exterior, 53 note
Area inferior, 53 note
Area media, 53 note
Area superior, 53 note
Areas of the wing, 53
Aurelia, 94 note
Auriculo-ventricularice, 69 note
Aristatce, 39 note
Back plate, 28
Back scale, 30
Band, 53
Basal meshes, 53
Basis, 53 note
Bile vessels, 63
Blight, 89
Blind gut, 64
Blow fly and Bot maggots, 91
Brain and spinal cord in man, 75
Breast-plate, 23
Breast-prop, 26
Breathing, organs of, 70
Breathing, process of, 72
Bridle, 31
Bulbus, 37 note
Calcaria, 48 note
Cardia, 63 note
Caterpillar, meaning of the term,
90
Cauda, 54 note and 57 note
Cellulae basilares, 53 note
Cellules exteriores, 53 note
Cellulee mediae, 53 note
Cerebrum ganglionicum, 76 note
Chaperon, 23 note
Cheese hoppers and Crane fly
grubs, 91
Chitine, chemical properties of, 22
Choroides, 40 note
Chrysalis, 94 note
Chyle gut, 64
Cilice, 54 note
Circulation of the blood traced, 70
Circulation, organs of, 66
Circumference of the wing, 53
Cleaning instrument, 58
Cocoon, or preparatory nest, 94
Caecum, 64 note
Coleoptera, 103 note
Collum, 23 note
Comb and sucker, 49
Cord and pulley mechanism, 35
Corium, 21 note
Cornea, 40 note
Corselet in insects, 2
Costa, 51 note
Costa anterior t 51 note
106
Costa inferior, 52 note
Costa internet, 52 note
Costa media, 52 note
Costa mediastina, 52 note
Costulse marginales, 52 note
Coxa, 27 and 48 note
Crop or crown, 62
Cubitus, 52 note
Cutis vera, 21 note
Dangerous errors of the natural
system in botany, 100
Development, abuse of the term,
87
Digestion, organs of, 59
Diptera, i 03 note
Discovery by M. Ehrenberg, 83
Dorsal vessel, 66
Duodenum, 64 note
Ears of insects, 21
Ears mistaken for organs of touch,
80
Earwigs and ants, 89
Edge rib and its hook, 51
Egg glue and its use, 85
Eggs of insects, 87
Eggs of the cockchafer, 48
Eggs of the gnat built into a boat,
87
Eggs of the louse, 84
Eggs traced in the body of the
mother, 84
Elytra, 54 note
Entothorax, 26 note
Epidema, 50 note
Epidema insertionis, 33 note
Epidermis, 21 note
Epimera, 27 note
Episterna, 27 note
ETriTo/xa, 23 note
Errors of the learned and the un-
learned, 85
Errors refuted, 83
Eruca, 90 note
Excrementu, 65 note
Eyelet, 53
Eyes of insects, 39
Faces, 65 note
Family, term objected to, 100
Fascia, 54 note
Fashionable systems rejected, 101
Fauces, 60 note
Feelings of insects not acute, 79
Feelers outer and inner, 44
Femur, 48 note
Flanks upper and under, 27
Foot, 48
Forceps, 57 note
Fountains of the mouth, 60
Frcenum, 56 note
Frangles and tail of the wings, 54
Funiculus, 35 note
Furca, 26 note
Galea, 44 note
Ganglionic brain in insects, 76
Ganglionic system in man, 76
Ganglion described, 76
Ganglion secundum, 77 note
Ganglion tertium, 77 note
Gastric vessels, 63
Gizzard, 62
Gooseberry and cabbage caterpil-
lars, 90
Growth of insects, 87
Grub, meaning of the term, 91
Gullet and its nervous ring, 62
Gullet ring and second ganglion,
77
Halteres, 56 note
Haunch, 48
Haus, 60
Head in insects, 22
Hearing, sense of, 80
Heart, or dorsal vessel, 66
Hemiptera, 103 note
Hibernian blunders respecting
moths, 100
Homaloptera, 103 note
Homoptera, 103 note
Honey bag of bees and butterflies,
62
Horn scale, 28
Horny wings of beetles, 54
Hymenoptera, 102 note
Imago, 95 note
Image as objectionable as the si-
milar term type, 95
Imperfect insects ! ! 96
Ineunabulum, Q4 note
Infancy of insects, 90
Ingluvies, 62 note
Inner rib, 53
Insect, meaning of the term, 17
Insects' mouths " imperfect " and
" totally useless" ! ! ! ! 42, 43
INDEX.
107
Instruments of female grasshop-
pers, saw-flies, and gall-flies, 85
Intestines, 64
Intestina, 64 note
Intestinum tenue, 64 note
Irr&ratia, 54 note
Jaws of insects, 43
Kingdom, animal, term objected
to, 100
Labium, 44 note
Labrum, 43 note
Lamellata;, 39 note
Larva, 92 note
Larva, a fanciful and objection-
able term, 92
Leathery wings of locusts, 55
Legs in insects, 47
Lepidoptera, 102 note
Lingula, 44 note
Linnaeus, confused system of, 101
Linnaeus, system misrepresented
by the disciples of, 99
Linnaeus, objectionable terms used
by, 95
Lower area, 53
Lower rib, 53
Macula, 54 note
Maggot, meaning of the term, 91
Male insects never assist the fe-
male, 82
Mandibulte, 43 note
Marginal ribs, 54
Margo anterior, 53 note
Margo exterior, 53 note
Margo inferior, 53 note
Mawks and gentles, 92
Maxillce, 43 note
Mechanism to aid the muscles
and wings, 32
Members of insects, 37
Mentum, 44 note
Mesathorax, 25 note
Meshes of the wing, 53
Mesosternum, 26 note
Metamorphoses more objection-
able than "transformations, "87
Metasternum, 26 note
Metathorax, 23 note
Mid area, 53
Mid meshes, 53
Mid rib, 52
Miner, Mason, and 'Carpenter in-
sects, 85
Motions of the abdomen, 35
Mouth in bees and in butterflies,
45
Mouth of insects, 42
Mouth in two-winged flies and
gnats, and bugs, 46
Muscles of insects, 36
Natural system, dangerous errors
of, 100
Nerve-knot described, 76
Nerves of the eyes, 81
Nervi optici, 81 note
Neurce, 5 1 note
Neuroptera, 102 note
Night insects, 41
Nutrition, 65
Ocelli, 39 note
Ocellus, 54 note
Oculi compositi, 39 note
(Esophagus, 62 note
Offensive discharges — Poison, 65
Organs, internal, 59
Orthoptera, 103 note
Ovarium, 84 note
Ovipositores, 58 note
Ovipositors, 58
Outer meshes, 53
Outlet of the stomach, 63
Palpi, 44 note
Palpi externi, 44 note
Palpi interni, 44 note
Paraglossa, 44 note
Parapteron, 27 note
Parasite of cuckoo flies, 85
Pec tines, 49 note
Pedes, 47 note
Perfect, abuse of the term,
Peritrema, 28 note
Pharynx, 60 note
Pigmeritum, 40 note
Plumules, 56 note
Prcescutum, 30 note
Poisers, 54
Postfurca, 26 note
Prehensores, 90 note
Profurca, 26 note
Propedes, 90 note
Proportion, law of, 15, 42, 47, 56
Prosternum, 26 note
Prothorax, 25 note
108 IN
Pupa, 95 note
Pupum, 95 note
Pylorus, 63 and 64 note
Radius, 51 note
Ramuli, 72 note
Reproduction, organs of, 82
Rectum, 6s note
Rete mucosum, 21 note
Rotula, 48 note
Scale feathers, 56
Scutellum, 30 note
Scutum, 30 note
Segmentum, 34 note
Senses, 79
Sensation, organs of, 45
Sericteriu, 60 note
Sexes, difference of in size and
colour, 83
Shank, 48
Shell expansive, 88
Short life of adult insects, 96
Sialisteria, 60 note
Silk organs, 60
Singularities in bees, wasps, and
ants, 82
Skin of insects, 20
Small gut and its functions, 64
Smell, sense of, 80
Speisesack, 62 note
Spiracula, 71 note
Spicula, 58 note
Spiracles, 71
Spiracula composita, 72 note
Spiracula simplicia, 71 note
Stemmata, 39 note
Sternum, 25 note
Stigma, 52 note
Stigmata, 71 note
Sting, 58
Stomach, 63
Streak, 53
Striga, 54 note
Systematic arrangement of in-
sects, 99
Systems all imperfect, 100
Systems lead to serious errors, 99
System, use of, 99
Tail, 53
Tail tuft, 57
Tail tweezers, 57
Tarsus, 48 note
Taste, sense of, 80
Tergum mesothoracis, 29 note
Tergum metathoracis, 29 note
Tergum prothoracis, 29 note
Tergum thoracis, 28 note
Thorax, 25 note
Thysanura, 104 note
Tibia, 48 note
Torulus, 37 note
Touch, sense of, 79
Tracheae, 54, 67, and 72 note
Tracheae tubulurice, 73 note
Trachea vesiculariee, 73 note
Trichoptera, 102 note
Trinity proved by the Trinarian
system, 99 note
Tremaeree, 72 note
Tribe, term objected to, 100
Trochanter, 48 note
Trochantina, 48 note
Trochlea, 35 note
Turnip fly, 90
Type an objectionable term,
Unguis, 49 note
Upper area
Valvula interventricularia, 69 note
Vent, 65
Vent gut, 65
Ventriculus callosus, 62 note
Ventriculus chylificus, 63 note
Vesicula dorsalis, 67 note
Vesicula biliarii, 63 note
Villi, 63 note
Vision, sense of, 81
Wing bridles, 54
Winglet, 54
Wing joint pieces, 50
Wing muscles, 50
Wing ribs or nervures, 51
Wings in insects, 49
Wing scale, 27
Wings supposed to be spiracles ! ! !
72
Wire worm, 91
" Worm i' the bud," 90
BRADBURY AND BVANS, PRINTERS, BOUVBRIE-STREBT, FLEET -STREET.