appropriated to alpine plants can only be met with where the pabulum
is found. Here also those northern insects that are impatient of
a warmer climate will take their station, if they migrate to the
southward[1518]. The predaceous beetles likewise sometimes frequent
a mountainous district. _Carabus glabratus_ was first taken by
Professor Hooker on Ingleborough; and probably, if the Welsh and
Scotch mountains were duly investigated by an Entomologist, many
novelties would reward his toils. The _valleys_ and _plains_,
especially those of a sunny exposition, abound in insects. When the
heat of the atmosphere indisposes you for motion, you will find it no
unprofitable or unpleasant employment, lying on the grass, to search
for minute beetles, which you will there find coursing about amongst
the tufts and roots of the herbage. Thus you may procure many of the
_Pselaphidæ_, which you would not otherwise meet with. Even when the
grass is grown up, insects are fond of alighting upon its spikes, and
thence drop or run to the ground. Should circumstances ever carry you
abroad to the steppes or grassy plains of Tartary, or to Hungary,
you would find there two or three species of the singular genus
_Lethrus_, which burrows in the soil. Every hole is inhabited by a
male and female;--from it they issue to attack the plants or vines;
and having cut out the heart of a plant, go backwards like a crab
with the prize to their burrow. At the time of pairing, sometimes
violent battles, encouraged by the female, take place between the
male and a stranger of that sex desirous of admission, which cease
only with the death or flight of the stranger[1519]. The vicinity and
borders of _woods_ generally abound in insects of every Order; and if
you proceed, as hereafter directed, will furnish you with numerous
prizes, especially of _Lepidoptera_. Here alone you can meet with the
purple emperor butterfly (_Apatura Iris_); and if properly equipped
you may readily secure him.
The _waters_ you will find nearly as prolific in insects as the
land. In them, amongst the beetles, you may expect to meet with
_Dytiscus_, _Haliplus_, _Pælobius_, _Hyphydrus_, _Hydroporus_,
_Noterus_, _Colymbetes_, and other _Dytiscidæ_; the _Gyrini_,
_Hydrophili_, _Hydrænæ_, _Elophori_, &c.: under stones, the _Elmis_;
and in the mud, the _Parni_ and _Heteroceri_. Some _Sphæridiadæ_ are
also aquatic: I have taken more than once _Cercyon hæmorrhoidale_
from the under side of a piece of wood immersed in a canal[1520].
Even a few of the weevil tribes are to be met with in water.
_Lixus paraplecticus_, _Tanysphyrus Lemnæ_, _Bagous atrirostris_,
are of this description. A species of _Ceutorhynchus_ of Germar's
_third_ family (_C. Natator_ K.) _swims_ well. On aquatic plants
you must look for _Helodes_ and the splendid _Donaciæ_, which,
living on submerged shoots and roots of these plants in their
larva state, continue to attend them when perfect. Amongst the
_Eutrech_in_a_[1521],--_Elaphrus_, _Notiophilus_, and _Bembidium_
frequent humid places, as the banks of rivers and ponds; and in such
a station, under the roots of _Potentilla anserina_, _Polygonum_,
&c. if you should be fortunate enough to find _Omophron limbatum_,
which connects the _Eutrech_in_a_ with the _Eunech_in_a_, you will
make a valuable addition to the list of British insects. In the
waters also you will meet with many Heteropterous _Hemiptera_; as
_Gerris_, _Hydrometra_, and _Velia_, and all the _Hydrocorisæ_ or
water-bugs. On aquatic plants the larvæ of some _Lepidoptera_ feed,
as _Hydrocampa stratiotata_, _potamogata_, &c. Those also of the
_Trichoptera_ must be sought for in the water: and if you should
feel inclined to see an interesting collection of their very curious
_cases_, Mr. Sheppard of Wrabness can gratify your curiosity. Though
few or no _Hymenoptera_ frequent this element, vast numbers of
_Diptera_ are there alone to be met with in their preparatory state,
particularly the gnats. We learn from Humboldt a curious fact with
respect to those of South America, or the _Zancudos_; that, with
some exceptions, these pests do not frequent those rivers called by
the natives _black waters_, but only those which they name _white
waters_[1522]. Of the _Aptera_, the genera _Hydrachna_, _Eylaïs_ and
_Limnochares_ are purely aquatic. Several spiders will walk over the
water; and one species (_Argyroneta aquatica_) inhabits it[1523]. The
_stagnant_ waters in your vicinity will produce different species
from _running_ ones. Thus _Haliplus elevatus_, &c. inhabits only
the _latter_, while the majority of the _Dytiscidæ_ abound most in
the _former_: the more minute ones may be sought for with success
amongst the duckweed that covers a pool. I do not recollect finding
any insect in waters absolutely _salt_[1524]; but _brackish_ waters
produce peculiar species: in these only, _Hydræna marina_ occurs; and
many of those large-eyed _Cimicidæ_ (_Acanthia_), as _A. saltatoria_,
_littoralis_, and _Zosteræ_ occur in places where salt water has
been. Latreille observes, that the genus _Pimelia_ is to be met with
only where the soil is impregnated with saline particles, or where
the species of the genus _Salsola_ abound[1525].
_Heaths_, though they do not afford numerous insects, have their
rarities. _Cicindela sylvatica_, _Carabus nitens_ and _arvensis_,
frequent them, and are not elsewhere to be seen. _Curculio nebulosus_
is also to be found on them, in places where the turf has been peeled;
and some scarce _Lepidoptera_. In their vicinity, in sunny sandy
banks, some of the rarer _Ammophilæ_ and _Pompili_ may be taken;
and it is here only that I have ever met with _Panurgus_[1526].
_Meadows_ and _pastures_ are not to be neglected. Early in the year,
when they are yellow with the blossoms of _Ranunculus bulbosus_,
_Leontodon Taraxacum_, &c., many minute beetles, and not a few
_Hymenoptera_ and _Diptera_, frequent them. _Morasses_ also have
their peculiar insects. In these you will meet with some of the
scarcer _Eutrech_in_a_; as _Chlænia holosericea_ and _nigricornis_,
_Blethisa multipunctata_, various _Bembidia_, &c. In this kind of
district in the Isle of Ely _Aphodius plagiatus_ has been taken, and
that scarce and beautiful butterfly _Lycæna Virgaureæ_. Where land
is _cultivated_ the Entomologist as well as the farmer may expect a
_harvest_. Insects in general are fond of perching on the summit of
a blade of grass or corn; and many minute ones may be taken coursing
about in the ears of the latter: some to devour the _fungilli_ that
infest the grain, as _Phalacrus corruscus_ in _Reticularia Segetum_;
others to attack the grain itself, as _Cecidomyia Tritici_; others to
destroy these destroyers, as three little parasites belonging to the
_Chalcidites_[1527]. But I have already mentioned most of those insects
that are to be expected in such situations[1528]: I shall therefore
only further observe, that upon _barley_ particularly you will meet
with the species of Latreille's genus _Cephus_.
With respect to _soils_, those that are _light_ appear to be most
prolific in insects. Warm _sandy_ banks are frequented by _Cicindela
campestris_, _Opatrum sabulosum_, _Helops quisquilius_, &c.: in them
(when of a southern aspect) _Ammophilæ_, _Pompili_, and numerous
_Hymenoptera_ nidificate. _Chalk_ also attracts various insects.
Latreille observes, that the _Licini_, _Papilio Cleopatra_, several
species of _Dasytes_, and some _Lamiæ_, delight in this kind of
soil[1529]:--in my own neighbourhood I have observed _Polyommatus
Corydon_ principally in chalk-pits. One of these pits, under a wood
in an adjoining parish, has produced me several valuable insects.
Here I took _Apion ebeninum_, _Orobitis globosus_, a new species of
_Evæsthetus_, several of the rarer _Pselaphidæ_ and _Cholevæ_, and
_Chætophorus cretifer_ before noticed[1530]. I do not mean, however,
that all these are properly _chalk_ insects; but they fall into these
pits, where they are readily discerned, from the contrast of their
colours with the whiteness of the chalk. By watching attentively the
bottom of one, vast numbers in a warm day may be taken when they
fall or are climbing upwards. Of all soils _clay_ offers the fewest
inducements to the Entomologist, who will lose both his time and labour
in a clay-pit; while in one of sand, chalk, or marl, they will usually
not be mispent. _Vegetable earth_ also affords a harbour to various
larvæ, and the pupæ of many nightfliers amongst the _Lepidoptera_,
by digging in it, especially under trees, may be obtained. Even the
bare _rocks_ have their insect frequenters that take shelter in
their fissures; and in the early part of your career especially you
should always turn over large stones, as beneath them many of the
_Harpalidæ_ and other _Eutrech_in_a_ frequently lie hid: and in this
situation, both in Suffolk and Sussex, _Lomechusa emarginata_, one
of our scarcest _Brachyptera_, has been taken. Old trees also, and
planks that have laid long without being moved, often afford a shelter
to many of the minute _Coleoptera_; as _Pselaphidæ_, _Aleocharidæ_,
_Cryptophagidæ_, _Scymnidæ_, &c. _Live_ fences, especially when
the hawthorn is in blossom, and where trees are also intermixed,
are attended by innumerable insects of almost every description;
and even the black-thorn will present you with one of our most
splendid weevils (_Rhynchites Bacchus_). _Dead_ fences are almost as
fertile in insects as living ones. In _gates_, _posts_, _rails_, and
other _timber_ when felled, the timber-devouring tribes take their
station:--between the bark and the wood are the _Bostrichidæ_; in
the wood itself, the _Anobidæ_ and the Capricorn beetles. Here also
you may meet with many _Hymenoptera_, which either devour timber or
nidificate in it,--as the _Siricidæ_, _Chelostoma_, _Trypoxylon_,
_Sapyga_, and several _Diptera_. In the decaying hedgestakes and
sticks, where the _Sphæria decorticans_ has turned off the bark, you
may meet with _Anthribus brevirostris_; with _A. latirostris_, and
other beetles, in _S. fraxinea_; and _A. albinus_, which I have more
than once captured as it was emerging from the fissure of a gate-post,
probably feeds on some internal fungus. The grassy _balks_ that
separate open fields usually abound in umbelliferous plants, which are
attended by numerous _Hymenoptera_ and _Diptera_, particularly by the
various species of the splendid tribe of _Chrysidæ_: and the grassy
banks of fences, where the aspect is sunny, are generally bored by a
variety of insects of the former Order, to prepare a nest for their
young. _Andrenidæ_ and _Nomadidæ_ particularly select this situation,
the latter probably depositing their eggs in the burrows of the
former[1531]. By watching these places in the spring, you may perhaps
have the good fortune to meet with a _Stylops_. It is singular, that
some insects choose, for their own residence or that of their young,
the hardest and most trodden pathways. Thus, some ants will build their
subterranean apartments under gravel walks; and so do many species of
the genus _Halictus_[1532], the habits and economy of which have been
so ably detailed by M. Walckenaër[1533]: _Cerceris_ also, and other
_Hymenoptera_, will choose such places, however public, for the site of
their nests or burrows. The ground is so consolidated by the constant
foot, that they, probably find such situations spare them a world of
labour, and therefore in their choice balance one inconvenience by
another.
Though the _sea_ itself, I believe, produces no true _insects_, yet
there are many that constantly or occasionally haunt its shores. On
the sand-hills of the Norfolk coast I found _Ægialia globosa_ and
_Cicindela hybrida_. _Ceutorhynchus horridus_ inhabits thistles that
grow near the sea. Under the _Zostera_ and _Fuci_, (cast up both on
its beach and the shores of estuaries,) many peculiar species of
_Cercyon_, several _Aphodii_, and numerous _Brachyptera_, may often
be found. In this situation the rare and singular _Bledius armatus_
has been taken. At certain seasons of the year the beach and environs
of the sea are covered by many species of _Coccinella_, which seem
to bend their course thither from the inland country, as if they
were about to emigrate[1534]. When the weather is fine and the tide
begins to retire, at the line of its highest rise I have taken on the
eastern coast a variety of insects, and amongst the rest _Anomala
Frischii_. The inundations of rivers, except in the depth of winter,
always bring a number of these little creatures, which float on the
surface on bits of stick, weeds, &c.; and where they deposit these
articles when the water begins to subside, you may generally reap a
plentiful harvest of various kinds.
You see, now, how varied is the scenery to which the diversion of
the Entomologist introduces him; that he is never out of his way:
whether on hill or in valley; on upland or plain; on the heath or in
the forest; on the land or on the water; in the heart of a country
or on its shores;--still his game is within his reach. But in order
to enable him to pursue it with greater prospect of success, he
must recollect that not only is every face of the country to be
explored, but both the _plants_ and the _animals_ that it produces;
and that he must not turn with disgust from even the _carcase_ or
the _excrement_ of the latter. As numerous species of herbivorous
insects feed only on _one_ kind of plant, the Entomologist, when he
discovers a scarce one, should examine it with the hope of finding
upon it a scarce insect. Sometimes it happens that only a single
opportunity occurs in a man's life of seeing certain plants growing
wild: such opportunities should never be neglected. Some insects also
inhabit a plant in one district or season, and not in another. Thus
the most beautiful of the Apions, _A. Limonii_[1535], though the
plant it feeds upon usually abounds near the sea, I have discovered
only on the northern coast of Norfolk; and another scarcely less
beautiful, but more minute (_A. Astragali_[1536]), though I have
sought for it year after year, _Astragalus glyciphyllus_ being
abundant near me, I never found but once. The blossoms of plants
as well as the leaves must be inspected. In those of the rose,
the _Cetonia aurata_ is often taken[1537]; and in the bells of
the different species of _Campanula_ various bees may be captured
enjoying a luxurious repose[1538]. No vegetable productions abound
more in insect inhabitants than the _Fungi_. In Agarics several
_Diptera_ are to be taken, many _Aleocharæ_, _Oxypori_, &c.; in
Boleti, the various species of _Mycetophagus_; in the arboreous ones,
and under bark, more than one kind of _Ips_; and in _Auricularia_, as
well as _Boletus_, the whole genus _Cis_. Upon _living_ Vertebrate
animals you must look for _Pulices_, _Pediculi_, _Nirmi_, _Acari_,
and many _Diptera_, as _Œstrus_, _Tabanus_, _Stomoxys_, and the
_Pupipara_ of Latreille; and on the garden-snails for that curious
genus _Drilus_, and some _Acari_[1539]. The caterpillars and pupæ of
_Lepidoptera_, &c. will, as you have heard, furnish you with numerous
ichneumons[1540]. On _dead_ animals you will find the various
species of _Silphidæ_, _Nitidulidæ_, _Dermestidæ_, _Byrrhidæ_,
_Chlolevidæ_, _Staphilinidæ_, _Muscidæ_, &c.; and in excrement,
various _Scarabæidæ_, _Histeridæ_, _Aphodiadæ_, _Sphæridiadæ_, the
_Brachyptera_ in general, and several _Diptera_[1541]. In putrescent
roots and fruits, as the turnip, the cucumber, &c., you may also
occasionally meet with rare _Coleoptera_.
* * * * *
I must next say something upon the _seasons_ of insects, and their
times of appearance. Those that collect honey and pollen are generally
among the first that proclaim the approach of spring; and their
appearance may be dated from the blossoming of certain trees and plants
of common occurrence. Other plants, accompanied by peculiar insects,
blossom later; and so on till we arrive at the autumn. The _earliest_
insect-season commences with the flowering of the _sallow_ (_Salix
Caprea_) usually accompanied in the garden by that of the _crocus_ and
the _gooseberry_. Then is your time to collect many species of wild
bees and _Diptera_ not afterwards to be met with: and various other
insects now begin to emerge from their winter-quarters, or are produced
from the pupa. _Another_ and later season is marked by the general
blossoming of the butter-cup (_Ranunculus bulbosus_), accompanied by
the marsh-marygold (_Caltha palustris_) and ladies'-smock (_Cardamine
pratensis_); when you may hunt the pastures, meadows, and marshes with
success, and take some insects that do not show themselves later.
The coprophagous insects are now abundant. Amongst others, _Aphodius
testudinarius_, a perfectly _vernal_ species, is now only to be taken,
and usually flying. A _third_ insect-season indicated by Flora, and a
very prolific one, commences with the blossoming of the _hawthorn_,
when you must desert the meads for the inclosures. At this time all
nature begins to put on her gayest attire, and all her insect tribes
are now on the alert, and fill the air. They are almost universally
attracted by the sweet and lovely blossoms of the plant just named: so
that by examining them you may entrap some of every Order, and many
that during the year will appear no more. Even many of the saprophagous
insects will sip nectar from these flowers. The _umbelliferous_
plants proclaim the _fourth_ season of insects, particularly the wild
_carrot_ and _parsnip_. You will scarcely ever fail to find, if the
weather is genial, _Hymenopterous_ and _Dipterous_ insects of various
genera,--especially such as have a _short_ tongue,--engaged in
collecting the honey from those plants. Here you may take some of the
rarer _Chrysidæ_, _Crabronidæ_, _Cercerides_, &c., and occasionally
even _Coleoptera_. The _last_ insect-season may be dated from the
general flowering of the _thistle_ tribe. When these are in blossom is
the best time of all to collect the _humble-bees_ (_Bombus_[1542]), the
leaf-cutter bees (_Megachile_[1543]), and many other _Apiariæ_, which
alone by their long tongues can imbibe the honey and collect the pollen
of these flowers. The male humble-bees frequent them to the last, and
often seem as if they were intoxicated with their sweets.
But perhaps you may prefer considering the whole summer appearance
of insects as divided into _three_ principal seasons. This may thus
be done. Their _vernal_ season may commence _Florente Caprea_, and
end _Florente Oxyacantha_; their _summer_, _Florente Oxyacantha_ and
_Florentibus Umbellatis_; their _autumn_, _Florentibus Umbellatis_
and _Florente Carduo_. In the _first_, the number of insects will
be daily _increasing_; in the _second_ (which is the harvest of the
Entomologist, when his eyes and his hands ought to be every where),
they will reach their _utmost complement_; and in the _third_, they
will be gradually decreasing in number, till they generally die,
or go into winter-quarters. At this time many minute _Diptera_ and
Ichneumons take shelter from the weather in the windows of our
apartments. These seasons will not always exactly correspond with
our usual reckoning, and take place at the same time; since, being
regulated by our varying temperature, they will be sometimes sooner
and sometimes later, sometimes longer and sometimes shorter. Though
I have not named a _brumal_ season, because insects are in winter
usually torpid,--yet some, as _Diurnea Novembris_, _Cheimatobia
brumata_, and many _Tipulariæ_, even then make their appearance.
If you ask, Whether it be not possible to regulate our Entomological
seasons by the appearance of insects themselves? I should answer,
that probably this might be done; but that further observations seem
wanted to enable us to do it satisfactorily. Perhaps the appearance
of _Formica rufa_ beginning the business of the year might form the
commencement of one season; the flight of the orange-tip butterfly
(_Pontia Cardamines_[1544]), of a second; a third might be indicated by
the swarming of _Melolontha vulgaris_; a fourth, by that of _Amphimalla
solstitialis_; and the last, by the appearance in numbers of _Aphodius
ciliaris_, which in the autumn fills every horse-dropping.
Some insects are so ephemeral, that they are to be found in numbers
only for a few days, and then disappear for that season. Of this
description are the _Ephemeræ_, much of whose history has been detailed
to you. Those of which De Geer has given an account (_E. vulgata_)
appeared about the end of May or the beginning of June, and continued
about a _fortnight_[1545]; while those which Swammerdam observed
did not come forth till the middle of June, and lasted only _three_
days[1546]. The _same_ period distinguished those of which Reaumur has
compiled so interesting a history, but they did not show themselves
before the middle of August[1547]. My kind friend Mr. Marsham not long
before his death copied for me some memoranda he had made with respect
to the sudden appearance of _Cercopis bifasciata_. On one occasion
the white dress of a lady sitting upon a haycock was covered by these
insects; but on the following day the same steps were taken at the same
time to procure some, when after the most diligent search not a single
one could be found. The same circumstance was observed a few years
afterwards by another friend of his. He himself was of opinion that the
insects in question were then migrating[1548].
I may here observe, that the London amateurs have particular _seasons_
for collecting _moths_. For the _imago_ they go into the woods in
_April_, _May_, _June_, and _October_. For the _larvæ_ they take the
beginning of _April_, _June_, the beginning of _July_, and _September_.
They dig for _pupæ_ late in _July_, and in _January_ and _February_.
* * * * *
I shall lastly make a few observations upon the _times_ of _action_
and _repose_ of insects, the knowledge of which, as far as it can
be obtained, is of essential use to the industrious collector.
Entomologists have divided the _Lepidoptera_, with a view to this
circumstance, into _diurnal_, _crepuscular_, and _nocturnal_; or
butterflies (_Papilio_ L.), hawkmoths (_Sphinx_ L.), and moths
(_Phalæna_ L.). These terms may be applied to insects in general.
i. _Diurnal_ insects are abundant. _Butterflies_ in particular fly
generally at no other time: they accompany the sun in his course, and
before he sets disappear. Some other _Lepidoptera_, though not so
named, are _day_ insects:--such are the _Zygænidæ_, &c. amongst the
hawkmoths; and amongst the moths, _Plusia Gamma_, the _Phytometræ
solares_ of Haworth[1549], and some others. Numberless _Coleoptera_
belong to this section. The _Donaciæ_ fly only when the sun is out
and the air is warm; they are then extremely agile and difficult
to take. Some _Hopliæ_ swarm in the day before noon, and then
disappear[1550]: most of the _tetramerous_ beetles also appear to be
diurnal. The _Libellulina_ and many other _Neuroptera_ may also be
so termed; and the _Hymenoptera_ almost universally, with the sole
exception of the _Formicidæ_[1551]. Amongst the _Diptera_, if we
leave out the _Tipulariæ_, the rest will be found for the most part
to belong to the present section.