endeavour to trace it in the country in which it received its name
and character. This country was certainly Greece; and there such
an animal, retaining nearly its old name, and accused of being the
cause of the same injury to cattle, still exists. For Belon informs
us that on Mount Athos there is found a winged insect like the
blister-beetle, but yellow, larger, and of a very offensive smell,
which feeds upon various plants, and is called _Voupristi_ by the
Caloyers or Monks, who assert that when horses or other cattle even
feed upon the herbs which the animals have touched, they die from
inflammation, and that it is an immediate poison to oxen[250]. This
therefore most probably was the Buprestis of the Greek writers;
and as Pliny usually compiled from them, it may be regarded as
his also, which he tells us was a caustic insect and prepared in
the same manner as the blister-beetle[251]. He further observes
that it was scarce in Italy. The Greek insect of Mount Athos M.
Latreille supposes to be a Mylabris, and in this I agree with him;
and therefore this is the proper genus to which the original Greek
Buprestis, the true type of the insect in question, ought to be
referred, and not Melöe.
Whether this animal be really guilty to the extent of which it is
accused, admits of considerable doubt; but as I have not the means
of ascertaining this, I shall leave the question for others who are
better informed to decide.
But, of all our cattle none are more valuable and important to us than
our _flocks_; to them we look not only for a principal part of our
food, but also for clothing and even light. Thick as is their coat of
wool, it does not shield them from the attack of all-subduing insects:
on the contrary it affords a comfortable shelter to one of their
enemies of this class, regarded by Linné as a species of _Hippobosca_,
but properly separated from that genus by Latreille under the name of
_Melophagus_[252]. This is commonly called the sheep-louse, and is so
tenacious of life, that we are told by Ray it will exist in a fleece
twelve months after it is shorn, and its excrements are said to give
a green tinge to the wool very difficult to be discharged.--You have
doubtless often observed in the heat of the day the sheep shaking
their heads and striking the ground violently with their fore feet; or
running away and getting into ruts, dry dusty spots or gravel pits,
where crowding together they hold their noses close to the ground.
The object of all these actions and movements is to keep the gad-fly
appropriated to them (_Œ. Ovis_) from getting at their nostrils, on
the inner margin of which they lay their eggs, from whence the maggots
make their way into the head, feeding in the maxillary and frontal
sinuses on the mucilage there produced. When full-grown, they fall
through the nostrils to the ground and assume the pupa. Whether the
animal suffers much pain from these troublesome assailants is not
ascertained. Sometimes the maggots make their way even into the brain.
I have been informed by a very accurate and intelligent friend, that,
on opening the head of one of his sheep which died in consequence of
a vertigo, three maggots were found in it in a line just above the
eyes, and that behind them there was a bladder of water.--Perhaps you
are not aware that the bots we are speaking of, or rather those in the
head of goats, have been prescribed as a remedy for the epilepsy, and
that from the tripod of Delphos. Yet so we are told on the authority of
Alexander Trallien. Whether Democrates, who consulted the oracle, was
cured by this remedy does not appear; the story shows however that the
ancients were aware of the station of these larvæ.--The common saying
that a whimsical person is _maggoty_, or has got _maggots in his head_,
perhaps arose from the freaks the sheep have been observed to exhibit
when infested by their bots.--The flesh-fly is also a great annoyance
to the fleecy tribe, especially in fenny countries; and if constant
attention be not paid them, they are soon devoured by its insatiable
larvæ. In Lincolnshire, the principal profit of the druggists is
derived from the sale of a mercurial ointment used to destroy them.--In
tropical countries the sheep frequently suffer from the ants. Bosman
relates that when in Guinea, if one of his was attacked by them in the
night, which often happened, it was invariably destroyed, and was so
expeditiously devoured that in the morning only the skeleton would be
left.
Of our domestic animals the least infested by insects, I mean as
to the number of species that attack it, is the _swine_. With the
exception of its louse, which seems to annoy it principally by
exciting a violent itching, it is exposed to scarcely any other
plague of this class, unless we may suppose that it is the biting of
flies, which in hot weather drives it to "its wallowing in the mire."
Under this head we may include the _deer_ tribe, for, though often
wild, those kept in parks may strictly be deemed domestic; and the
rein-deer is quite as much so to the Laplander, as our oxen and kine
are to us. We learn from Reaumur that the fallow-deer is subject to
the attack of two species of gad-fly[253]: one, which, like that
of the ox, deposits its eggs in an orifice it makes in the skin of
the animal, and so produces tumours; and another in imitation of
that of the sheep, ovipositing in such a manner that its larvæ when
hatched can make their way into the head, where they take their
station in a cavity near the pharynx. He relates a curious notion
of the hunters with respect to these two species. Conceiving them
both to be the same, they imagine that they mine for themselves a
painful path under the skin to the root of the horns; which is their
common rendezvous from all parts of the body; where, by uniting
their labours and gnawing indefatigably, they occasion the annual
casting of these ornamental as well as powerful arms. This fable,
improbable and ridiculous as it is, has had the sanction of grave
authorities[254].--The Œstri last mentioned inhabit, in considerable
numbers, two fleshy bags as big as a hen's egg, and of a similar
shape, near the root of the tongue. Reaumur took between sixty and
seventy bots from one of them, and even then some had escaped. What
other purpose these two remarkable purses are intended to answer, it
is not easy to conjecture. He supposes that the parent fly must enter
the nostrils of the deer, and pass down the air passages to oviposit
in them: but probably such a manœuvre is unnecessary, since there
seems no reason, supposing the eggs to be laid in the nostrils, why
the larva when hatched cannot itself make its way down to the above
station, as easily as that of the sheep into the maxillary sinuses.
Or, which perhaps is more likely, when the animal draws in the air,
the eggs or larvae may be carried down with it, in both cases, to the
place assigned to them by Providence[255].
No animal, however, is so cruelly tormented by Œstri as the
_rein-deer_; for besides one synonymous apparently with this of the
deer (_Œ. nasalis_) from which they endeavour to relieve themselves
by snorting and blowing[256], they have a second which produces bots
under their skin; not improbably the same species that in a similar
way attacks the latter, as I have stated above. We have heard that
the vaccine disease is derived from the cow and the horse, and the
small-pox is said to have originated in the heels of the camel: but
neither the ingenious Dr. Jenner nor any other writer on this subject
has informed us that the rein-deer is subject to the distemper last
named; yet Linné quotes the learned work of a Swedish physician on
_Syphilis_, who gravely gives this as a fact[257]!! The inoculator,
in truth, is the gad-fly, the tumours it causes are the pustules,
and its larvæ are the pus.--It is astonishing how dreadfully these
poor animals in hot weather are terrified and injured by them: ten
of these flies will put a herd of five hundred into the greatest
agitation. They cannot stand still a minute, no not a moment, without
changing their posture, puffing and blowing, sneezing and snorting,
stamping and tossing continually; every individual trembling and
pushing its neighbour about. The ovipositor of this fly is similar
to that of the ox-breese, consisting of several tubular joints which
slip into each other; and therefore Linné was probably mistaken in
supposing that it lays its eggs _upon_ the skin of the animal, and
that the bot, when it appears, eats its way through it[258]: there
can be little doubt (or else what is the use of such an apparatus)
that it bores a hole in the skin and there deposits the eggs. About
the beginning of July the rein-deer sheds its hair, which then
stands erect--at this time the fly is always fluttering about it, and
takes its opportunity to oviposit. The bots remain under the skin
through the whole winter, and grow to the size of an acorn. Six or
eight of these are often to be found in a single rein-deer that has
only seen one winter; and these so emaciate them, that frequently one
third of their number perish in consequence. Even those that are full
grown suffer greatly from this insect. The fly follows the animals
over precipices, valleys, the snow-covered mountains, and even the
highest alps; to which in order to avoid it they often fly with great
swiftness in a direction contrary to the wind. By this constant
agitation and endeavour to escape from the attack of their enemy they
are kept from eating during the day, standing always upon the watch,
with erect ears and attentive eyes, that they may observe whether it
comes near them[259]. The rein-deer are teased also by a peculiar
species of Tabanus (_T. tarandinus_) which, by a singular instinct,
instead of their skin, makes its incision in their horns when tender.
Our _dogs_, the faithful guardians of our other domestic animals and
possessions, the attached companions of our walks, and instruments of
many of our pleasures and amusements, cannot defend themselves from
insect annoyance. They have their peculiar louse, and the flea sucks
their blood in common with that of their master: you must also often
have noticed how much they suffer from the dog-tick, which, when once
it has fixed itself in their flesh, will in a short time, from the
size of a pin's head, so swell itself out by gorging their blood,
that it will equal in dimensions what is called the tick-bean. In
the West Indies these ticks, or one like them, get into the ears
and head of the dogs, and so annoy them and wear them out that they
either die or are obliged to be killed[260].
Some of the most esteemed dainties of our tables are supplied from
such of the winged part of the creation as we have domesticated.
These also have a louse (_Nirmus_) appropriated to them, and the
gorgeous peacock is infested by one of extraordinary dimensions
and singular form[261]. Pigeons, in addition, often swarm with the
bed-bug, which makes it advisable never to have their lockers fixed
to a dwelling-house. In their young, if your curiosity urges you
to examine them, you may find the larva of the flea, which in its
perfect state often swarms in poultry.
Amongst our most valuable domestic animals I shall be very unjust
and ungrateful, if I do not enumerate those industrious little
creatures the _bees_, from whose incessant labours and heaven-taught
art we derive the two precious productions of honey and wax.
They also are infested by numerous insect-enemies, some of which
attack the bees themselves, while others despoil them of their
treasures.--They have parasites of a peculiar genus, although at
present regarded as belonging to Pediculus[262], and mites (_Gamasus
gymnopterorum_) are frequently injurious to them. That universal
plunderer the wasp, and his formidable congener the hornet, often
seize and devour them, sometimes ripping open their body to come
at the honey, and at others carrying off that part in which it is
situated. The former frequently takes possession of a hive, having
either destroyed or driven away its inhabitants, and consumes all
the honey it contains. Nay there are certain idlers of their own
species, called by apiarists corsair-bees, which plunder the hives
of the industrious.--From the curious account which Latreille has
given us of _Philanthus apivorus_, a wasp-like insect, it appears
that great havoc is made by it of the unsuspecting workers, which it
seizes while intent upon their daily labours, and carries off to feed
its young[263]. Another insect, which one would not have suspected
of marauding propensities, must here be introduced. Kuhn informs us,
that long ago (in 1799) some monks who kept bees, observing that
they made an unusual noise, lifted up the hive, when an animal flew
out, which to their great surprise no doubt, for they at first took
it for a bat, proved to be the death's-head hawk-moth (_Acherontia
Atropos_), already celebrated as the innocent cause of alarm[264];
and he remembers that several, some years before, had been found dead
in the bee-houses[265]. M. Huber, also, in 1804 discovered that it
had made its way into his hives and those of his vicinity, and had
robbed them of their honey. In Africa we are told it has the same
propensity; which the Hottentots observing, in order to monopolize
the honey of the wild bees, have persuaded the colonists that it
inflicts a mortal wound[266]. This moth has the faculty of emitting
a remarkable sound, which he supposes may produce an effect upon the
bees of a hive somewhat similar to that caused by the voice of their
queen, which as soon as uttered strikes them motionless, and thus it
may be enabled to commit with impunity such devastation in the midst
of myriads of armed bands[267]. The larvæ of two species of moth
(_Galleria Cereana_, and _Mellonella_) exhibit equal hardihood with
equal impunity. They indeed pass the whole of their initiatory state
in the midst of the combs. Yet in spite of the stings of the bees
of a whole republic, they continue their depredations unmolested,
sheltering themselves in tubes made of grains of wax, and lined with
silken tapestry, spun and wove by themselves, which the bees (however
disposed they may be to revenge the mischief which they do them, by
devouring, what to all other animals would be indigestible, their
wax,) are unable to penetrate. These larvæ are sometimes so numerous
in a hive, and commit such extensive ravages, as to force the poor
bees to desert it and seek another habitation.
I shall not delay you longer upon this subject by detailing what
_wild animals_ suffer from insects, further than by observing
that the two creatures of this description in which we are rather
interested, the _hare_ and the _rabbit_, do not escape their attack.
The hare in Lapland is more tormented by the gnats than any other
quadruped. To avoid this pest it is obliged to leave the cover of
the woods in full day, and seek the plains: hence the hunters say,
that of three litters which a hare produces in a year, the first
dies by the cold, the second by gnats, and only the third escapes
and comes to maturity[268].--We learn from the ingenious Mr. Clark,
that the American rabbit and hare are infested by the largest species
of Œstrus[269] yet discovered; and our domestic rabbits sometimes
swarm with the bed-bug. This was the case with some kept by two young
gentlemen at my house last summer to such a degree, that I found it
necessary to have them killed.
Nor are the _inhabitants of the waters_ sheltered by their peculiar
element from these universal assailants. The larvæ of Dytisci fixing
themselves by their suctorious mandibles to the body of _fish_,
doubtless destroy an infinite number of the young fry of our ponds.
Some species of salmon (_Salmo Fario_, L.) are the food of an animal
which Linné has arranged under Pediculus; and probably many others of
the finny tribes may, like the birds, have their peculiar parasites.
Even _shell-fish_ do not escape, for the _Nymphon grossipes_ enters
the shell of the muscle and devours its inhabitant.
I am, &c.
FOOTNOTES:
[231] See above, p. 110.
[232] Once travelling through Cambridgeshire with a brother
entomologist in a gig, our horse was in the condition here described,
from the attack of _Tabanus rusticus_.
[233] De Geer, vii. 158.
[234] See Mr. W. S. MacLeay in _Linn. Trans._ xiv. 355--.
[235] De Geer, vi. 295.
[236] _Amœn. Acad._ iii. 358.
[237] Linn. _Flor. Lapp._ 376. _Lach. Lapp._ i. 233, 234. This insect
from Linné's description is probably no _Culex_, but perhaps a
_Simulium_, Latr. (_Simulia_, Meig.).
[238] _Life of General Thomas_, 186.
[239] Linn. _It. Scand._ 182. De Geer, v. 227-30.
[240] PLATE XVI. FIG. 3. Mr. Clark, however, is of opinion that the
Œstrus does not pierce the skin of the animal, but only glues its
eggs to it. _Essay on the Bots of Horses and other Animals_, p. 47.
[241] Much of the information here collected is taken from Reaum. iv.
_Mem._ 12; and Clark in _Linn. Trans._ iii. 289.
[242] The writer of the present letter is possessor of this specimen,
which he took on himself in a field where oxen were feeding. PLATE V.
FIG. 1.
[243] In the _Systema Antliatorum_ (p. 56) Fabricius most strangely
considers this insect as synonymous with _Culex reptans_, L. calling
it _Scatopse reptans_, and dropping his former reference to Pallas,
and account of its injurious properties. Meigen (_Dipt._ i. 294)
makes this insect a _Simulia_ under the name of _S. maculata_.
[244] Fabr. _Ent. Syst. Em._ iv. 276. 22. Latr. _Hist. Nat._ &c. xiv.
283. _Leipz. Zeit._ Jul. 5, 1813, quoted in Germar's _Mag. der Ent._
ii. 185.
[245] It is by no means clear that the _Œstrus_ of modern entomologists
is synonymous with the insects which the Greeks distinguish by that
name. Aristotle not only describes these as _blood-suckers_ (_Hist.
Animal._ l. viii. c. 11.) but also as furnished with a _strong
proboscis_ (l. iv. c. 7.). He observes likewise that they are produced
from an animal inhabiting the _waters_, in the vicinity of which
they most abound (l. viii. c. 7.). And Ælian (_Hist._ l. vi. c. 38.)
gives nearly the same account. Comparing the Œstrus with the Myops
(synonymous perhaps with _Tabanus_, Latr., except that Aristotle
affirms that its larvæ live in wood, l. v. c. 19,) he says, the Œstrus
for a fly is one of the largest; it has a stiff and large sting,
(meaning a proboscis,) and emits a certain humming and harsh sound--but
the Myops is like the Cynomyia--it hums more loudly than the Œstrus,
though it has a smaller sting.
These characters and circumstances do not at all agree with the
modern Œstrus, which, so far from being a blood-sucker furnished
with a strong proboscis, has scarcely any mouth. It shuns also the
vicinity of water, to which our cattle generally fly as a refuge from
it. It seems more probable that the Œstrus of Greece was related to
Bruce's _Zimb_, represented in his figure with a long proboscis,
which makes its appearance in the neighbourhood of rivers, and
belongs to the _Tabanidæ_. For further information the reader should
consult Mr. W. S. MacLeay's learned paper on the insect called
_Oistros_ and _Asilus_ by the ancients. _Linn. Trans._ xiv. 353--.
[246] Bruce's _Travels_, 8vo. ii. 315.
[247] Heb. זבוב בעל literally "Lord-Fly." See 2 Kings, i. 2; and
Bochart. _Hierozoic._ ps. ii. l. 4. c. 9. p. 490.
[248] _Burn-Cow_ or _Ox_, from βους bos, and πρηθω inflammo. M.
Latreille translates it _Crève-bœuf_, but improperly.
[249] _Annales du Muséum_.--X^e Ann. N^o xi. p. 129.
[250] _Observations de plusieurs Singularités, &c._ l. i. c. 45. p.
73 of the Edition in Sir Joseph Banks's Library.
[251] _Hist. Nat._ l. xxix. c. 4.
[252] See Curtis, _Brit. Ent._ t. 142.
[253] Mr. Curtis (_Brit. Ent._ t. 106) under the name of _Œstrus
pictus_ has figured a fine species of Gad-fly taken in the New
Forest, which he conjectures may be bred from the Deer. It may
probably be one of the species here alluded to.
[254] Reaum. v. 69. _Dictionnaire de Trevoux_, article _Cerf_.
[255] For the account of the Œstrus, of the deer, see Reaum. v. 67-77.
[256] Linn. _Lach. Lapp._ ii. 45. In the passage here referred to,
Linné speaks of two species of Œstrus, though the mode of expression
indicates that he considered them as the same. One was _Œ. nasalis_
from which they freed themselves by snorting, &c., the other _Œ.
Tarandi_ which formed the pustules in their backs. In _Syst. Nat._
969. 3. he strangely observes under the former species, "_Habitat
in equorum_ fauce, per nares intrans!" confounding probably _Œ.
veterinus_ of Mr. Clark with the true _Œ. nasalis_.
[257] _Lach. Lapp._ i. 280.
[258] _Flor. Lapp._ 79.
[259] Linn. _Flor. Lapp._ 379.
[260] Mr. Kittoe.
[261] PLATE V. FIG. 3.
[262] _Melittophagus_, Mus. Kirby. See _Mon. Ap. Angl._ ii. 168.
I copy the following memorandum respecting _M. Melittæ_ from my
common-place-book, May 7, 1812. On the flowers of Ficaria, Taraxacum
and Bellis, I found a great number of this insect, which seemed
extremely restless, running here and there over the flowers, and over
each other, with great swiftness mounting the anthers, and sometimes
lifting themselves up above them, as if looking for something. One or
two of them leaped upon my hand. Near one of these flowers I found
a small _Andrena_ or _Halictus_, upon which some of these creatures
were busy sucking the poor animal, so that it seemed unable to fly
away. When disclosed from the egg, I imagine they get on the top of
these flowers to attach themselves to any of the _Andrenidæ_ that may
alight on them, or come sufficiently near for them to leap on it.--K.
[263] Latreille, _Hist. des Fourmis_, 307-20.
[264] See above, p. 34.
[265] _Naturforscher_ Stk. xvi. 74.
[266] Quoted from Campbell's _Travels in South Africa_, in the
_Quarterly Review for July_ 1815. 315.
[267] Huber. _Pref._ xi-xiii.
[268] De Geer, ii. 83.
[269] Considered by Mr. Clark as a new genus, which he has named
_Cuterebra_, and of which he has described three species. _Essay on
the Bots of Horses, &c._ _p._ 63. _t._ 2. _f._ 24-29.
LETTER VI.
_INJURIES CAUSED BY INSECTS._
INDIRECT INJURIES CONTINUED.
Having endeavoured to give you some idea of the mode in which
insects establish and maintain their empire over man and his train
of dependent animals, I shall next call your attention to his
_living vegetable_ possessions, whether the produce of the forest,
the field, or the garden; whether necessary to him for his support,
convenient for his use, or ministering to his comfort, pleasure
and delight:--and here you will find these little creatures as
busily engaged in the work of mischief as ever, destroying what is
necessary, deranging what is convenient, marring what is beautiful,
and turning what should give us pleasure into an object of disgust.