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hairy, and is sometimes known by tho name of the palmer worm. The other is the
Miller, or Pot-lierb moth (iVóctua olerácea i l ) . Both those, as caterpillars, may be
seen, when about to become pupæ, crawling about in search of a place to undergo their
metamorpliosis. The caterpillar of Chaim'as gráminis Fab. is very destructive to pastures.
In 1769, and again in 1802, as Mr. Kirby states, “ the high sheep farms in
Twocddale were dreadfiüly infested by a caterpillar, which was probably of this species ;
spots of a mile square wore totaUy destroyed by them, and tho grass devoured to the
roots.”
1650. F n iit trees, and more particularly apple trees, are subject to the attacks of many
lepidopterous caterpillars. Independently of the various causes for blight, proceeding
from the soil and the weather, there are others entirely originating in insects. Gardeners
frequently observe that the tender leaves on the young apple and apricot shoots have the
appearance of being sewn or woven together, or rolled up and withered ; now, it is beyond
all doubt that neither heat, cold, nor fungi, have the least agency in causing these injuries.
They are, in fact, entirely produced by small caterpillars ; and if the leaves are
separated, and carefully unrolled, these depredators will be detected. One is of a
chestnut brown colour, with a black head ; another is green, with a few black hairs
scattered over its body, and both are the larvæ of different small moths.
1651. Other caterpillars which infest fr u it trees arc those of a little moth ( Tinea corti-
célia), which lives beneath the bai-k ; and the laiwæ of Tórtrix WoeberÔKa {Hort. Trans.,
vol. ii. p. 25.), by which is often laid the foundation of canker. Our fruit trees of different
kinds are often injured by the caterpillars of .Bombyx Neùstria the baived trce-
lackcy-moth, which live in large societies beneath a web-like tent. Linnæus calls the
Figure-of-eight moth (bomb y x cænileoccphala F.) the pest of Pomona. Reaumur lias
particularly noticed another species in Fi-ance ; which, from the observations of Mr.
Knight, appears to be found also in England (T in e a Pomonclla?). The catei-pillar of
this species feeds on the hcai't of the fniit, and thus causes it to fall in an unripe state.
The gooseben-y and currant trees in the gai-dens round London are terribly injured by
the black and white caterpillars of the Gooseberry moth ; and the chestnuts, pai-ticu-
larly in Fi-ance, are destroyed, while yet young, hy the lai-væ of a small moth, which eats
into the fruit. That pest of Flora, the Rose Tortrix (T. rosana), is produced from those
little green caterpillars found concealed in the curled or folded leaflets of the rose ; and a
still more pernicious kind enters the bud, and frequently destroys evei-y opening blossom.
1652. Other caterpillars, although not found in gardens, are prejudicial in vai-ious ways.
The lai-va of the ghost moth (Hepialus hùmuli F .) attacks and does much mischief to
the roots of the hop plant. The gigantic Goat moth (Cossus lignipérda F.), as a catcr-
pillai-, lives entirely within the tm u k of the willow, and soon brings it to decay : the
same tree is also inliabited by one of the clear-winged hawk moths (Sèsia crabroni-
forrais F.). A small moth (P y ralis secàlis F .) eats the culm of the rye within the
vagina, and thus destroys many ears ; whüe om- woollen garments, furs, feathers, and
even books, are sometimes ruined by the depredations of thi-ee or four other little moths,
unfortunately too well known in our dwellings.
1653. H e m i p t e r a . The chief chai-actcr of this order is that the mouth is in the foi-m
of a slender and lengthened proboscis, which, when not used, is folded beneath the breast,
but not coiled up, as in the lepidopterous insects. The wings are four, of unequal size,
two of whicli are always clear, and the others are generally semi-transparent. The
transforniations of this order resemble those of the Orthóptera, the larvæ and pupæ
being active and resembling the perfect insects except in wanting organs of flight. One
division of this order, the bugs ( Cimicidæ), feed upon other insects, by sucking thcir
juices, and are consequently in no respect injurious to gardens. The otlier division
feed upon vegetable juices, and among these we find the cicadas or frog-hoppers, tho
aphides, or plant-lice, and the cocci, or scale insects. Few of the larger or more remarkable
plant-sucking Hemiptera are found in Europe, but
tropical America produces some of the most whimsical and
grotesque foi-ms, as Membracis ensata {fig. 288. a a), M.
fuscata (6), and M. spinósa (c). The frothy secretion often seen
in summer upon different plants is caused by the larva of the
common frog-hopper (Aphróphora spumài-ia), a specimen of
which of a green colour is always to be found in the middle
of the mass.
1654. The Aphides, or Plant-lice {called by many the greenfly
), truly belong to the Hemiptera ; and, next to locusts,
they ai-e the most universal devastators of vegetables. Almost
every cultivated plant is attacked by them : and their fecundity
is so prodigious, that Reaumur has proved that, in five
generations, one apliis may be the progenitor of 5,904,900,000
descendants ; and it is supposed that in one year there may
be ten generations. This astonishing fecundity exceeds that of any other known animal ;
but some, especially those of wheat, oats, and barley, appear to multiply m a much less
degi-ce. The species arc numerous, and are appropriated to different plants. The
aphides wliich appear very early in the spring are produced from eggs deposited upon
the branches the preceding autumn, and hatched about the time that the buds begin to
unfold thcir first tender leaves. The first brood is, however, vivaparous— in other worfts,
producing its young alive ; and this continues during summer ; but towards autumn they
become oviparous : were not this the case, the cold of winter would cause their total extermination.
The most remarkable circumstance attending tlieir propagation is, that
the sexual intercourse of one original pair is sufficient for all the generations which proceed
fr-om the female for a whole succeeding year. Richardson thinks that all of the
first spring brood are females ; and if this supposition be con-ect, the rapid increase of
thcir numbers during April and May may be easily accounted for. Some writers say
that the larva, chrysalis, and perfect insects (all of which have legs), cannot be distinguished
fi-om each other ; and others consider that those without wings are the females :
there is reason, however, to think the reverse of this to be the case ; as it is well known
that, during summer, swarms of aphides may be seen on the wing, and are known to settle
on places not before infested by them; this is usually attended with the production of a new
colony, which must obviously come from the females. The injm-y they cause is produced
by sucking or pumping out the juices of the shoots by means of a long rostrum, which
usually lies inflected and concealed beneath the breast, and is enclosed in a sheath of
five joints. Those feeding upon the different kinds of pulse, and on flowering plants
in general, increase so rapidly, and take such entire possession of whatever they fix upon,
that vegetation is checked and often destroyed. Indeed, one species attached to tlie
potato has been asserted by Mr. Smce to be the real cause of the disease by wluch that
vegetable has been so extensively destroyed in several of the late seasons (1845-8).
This assertion has, however, been rejected by all the best vegetable physiologists. These
insects are exposed to many devouring enemies, which ai-e incessantly (though in a
great measure unobservedly) employed in thcir dcstmction. Eveiy gai-dener must have
seen span-ows and other small birds pecking them from rose hushes ; but his_ most
friendly coadjutor in this beneficial work is the gi-ub {fig. 289. b) of the lady-bird or
lady-cow (Coccinélla L .) {a). It is observed that vast numhers of
these interesting little beetles are generally seen in years when the
plant-louse abounds. Mr. Kirby states, that in 1807, the shore at
Brighton and on the south coast was literally covered with them, to
the great siu-prise and even alai-m of the inhabitants, who were ignorant
that their little visiters were emigrants from the neighbouring
hop-grounds, where, in their larva state, each had slain his thousands
and tens of thousands of the aphis, known to the hop-growers under
the name of the Fly. The larvæ of many real flics (Syrphus F.)
{fig. 289. c) make astonishing havoc among the aphides. “ I t was but
last week,” Mr. Kirby continues, “ that I obser\-ed the top of cyeiy
young shoot of the cuiTant-trecs in my gai-den curled up by myriads
of these insects. On examining them tliis day, not an individual remained ; but beneath
each leaf ai-e three or four fiill-fcd larvæ of aphidivorous flies sun-ounded with heaps ot
the skins of the slain ; and the young shoots, whose progi-css had been cntu-ely checked,
are again expanding vigorously.” {Int. to Entomology, vol. i. p. 226.) I h e destmctive
insect found on apple trees, known under the name of the American blight, is a species
of this family It is a minute insect covered with long cotton-like wool, and takes its
station in the chinks and hollows of the bark. I t there increases so rapidly, that, li not
destroyed, the tree to which it is attached will inevitably pensh.
1655 A p h i d e s a r e also the prey o f another most cruel enemy. This is a smaU hymenopterous
insect, which deposits its egg in their bodies : it is there hatched, and the lanra
feeds upon the bowels of the living insect ; in a short time the aphis swells, becomes
hard and changes to a dai-k red colour. The artful destroyer within, when he finds his
victiin dying, cats a hole through its belly, and fastens it by that part to a leaf or twig.
When the pai-asitc has thus devoured the inside, and is ready to emerge as a periect
insect he opens a passage for liimself, by cutting out a circular hole on the side, leaving
the piece attached to the body like a door on its hinges {fig. 290. m). Wa ll fruit trees,
as the peach, apricot, and nectarine, are considerably injured by other species of aphides,
which cause the leaves to rise into red tubercles ; under these they reside, and, by sucking
the sap they cause the leaves to curl, and thus deform the tree and injui-e the produce.
Ml- Swainson informs us of a fact, not generally known : that aphides are not found m
I . .1 -X io to rk i-« cnr>r>li<irl E v rn qm D v n ilS Rnf'.iMPS
289
South America; but that their place in nature is there supplied by numerous ^e cies
of Membrkis, Centrotus, &c. Lat. {fig. 288.), which are, in fact, theÎ p] lant-lice of that
contment.^^^^ Scale insects {Gócci) {fig. 290.) frequently produce as much