The _Aculeata_ contains the great majority of the _Hymenoptera_. Their
principal characteristic is that the ovipositor of the female in most
of the groups is modified into a sting. The _larvæ_ are footless grubs.
This tribe is divided into four sections, which are again subdivided
into seventeen families, each of which it is our intention to discuss
in their proper order.
_Section 1.--Anthophila._
_Family 1, Aphidæ._--This family contains the numerous species of honey
bees which are familiar to all of us. They are very varied in their
structure, colours, and habits. Many species are social, while many
others are solitary. The common Hive Bee (_Apis mellifica_) belongs to
the former class. There is, perhaps, no insect which has attracted so
much notice as this species. Volumes have been written respecting it,
and philosophers in all ages of the world's history have spent their
whole lifetime in the elucidation of its economy.
[Illustration: Fig. 7.--Megischus Annulator.]
[Illustration: Fig. 8.--Apis Mellifica (Queen).]
[Illustration: Fig. 9.--Apis Mellifica (Drone).]
In southern Europe, notably in Italy, a much brighter-coloured and
finer insect is found, distinguished especially by having yellow
transverse bands on the abdomen. This bee was long supposed to be a
distinct species, and was described under the name of _Apis ligustica_,
but it is now regarded as merely a variety. This bee has been
introduced into all the northern parts of Europe.
[Illustration: Fig. 10.--Apis Mellifica (Worker).]
Several species of Humble Bees are very common in this country. One of
the best known is the _Bombus terrestris_, the large females of which
may attain a length of nearly an inch. This is a large black insect
with the extremity yellow.
[Illustration: Fig. 11.--Melipona Anthidioides (Mag.)]
In another rather smaller species, _Bombus lucorum_, the extremity of
the abdomen is white. Both these species are subterranean bees, forming
their nests in banks, etc.
Of the moss-builders, the best known, perhaps, is the _Bombus
muscorum_, the largest specimens of which measure about two-thirds of
an inch long.
Another species, _Bombus lapidarius_, is so called from a preference it
shows for making its nests under stones. The end of the abdomen of this
bee is bright orange-red.
[Illustration: Fig. 12.--Bombus Pratorum.]
Of the solitary bees a very common black species is _Anthophora
acervorum_, which is usually found in abundance in the spring in the
neighbourhood of banks and cliffs.
The violet Carpenter Bee (_Xylocopa violacea_), which chiefly inhabits
the south of Europe, is a very pretty insect with violet-coloured wings.
[Illustration: Fig. 13.--Xylocopa Violacea.]
The Mason Bee (_Chalicodoma muraria_) builds its nest, composed of fine
grains of sand, very firmly united by a salivary secretion, upon the
surface of walls and similar situations. This species has hitherto not
been met with in this country.
The Horned Bee (_Osmia bicornis_) is remarkable for the female having
two little horns projecting from the front of her head. This insect
usually burrows in sandy banks and cliffs. Another allied species
(_Osmia hirta_) burrows in wood, whilst two others (_Osmia bicolor_ and
_aurulenta_) select ready-made nests in the shells of the common snails
(_Helix hortensis_ and _H. nemoralis_), within the whorls of which
they build their cells of gnawed vegetable material.
[Illustration: Fig. 14.--Ctenioschelus Latreillii.]
The Leaf-cutting Bees, which belong to the genus _Megachile_, are also
very interesting in their habits.
[Illustration: Fig. 15.--Osmia Tunensis.]
[Illustration: Fig. 16.--Andrena Collaris.]
_Family 2, Andrenidæ._--All the insects belonging to this family
are solitary in their habits. The species are very numerous in this
country. Many of them burrow in the ground, while others have been
observed to make their nests in bramble stick. They are usually smooth,
black insects, very unlike bees in appearance. The females have no
apparatus for carrying pollen either on the legs or on the abdomen.
_Section 2.--Diploptera._
_Family 3, Vespidæ._--The Social Wasps, which belong to this family,
are very well known everywhere in this country. In their general
structure they resemble the bees, but are usually much more slender in
appearance, and also much less hairy.
[Illustration: Fig. 17.--Polistes Gallica.]
The general habits of these wasps are pretty uniform except in the
matter of their architecture, and in this respect they display a
remarkable variety.
[Illustration: Fig. 18.--Nest of Polistes Gallica.]
Besides the common Wasp (_Vespa vulgaris_) two other species found in
this country, which build their nests in the ground, follow the same
principles in the construction of their nests.
The Hornet (_Vespa crabo_), which is remarkable for its large size,
usually builds its nest in the hollow of a tree. Both the hornet and
common wasp sometimes build their nests under the eaves of houses
or attached to a beam under the roof; and in these cases the outer
covering of the nest is thinner and more delicate in texture than
when the dwelling is exposed to the vicissitudes of the weather.
Another common species inhabiting Britain is the Wood Wasp (_Vespa
sylvestris_), which builds nests suspended from the branches of trees.
[Illustration: Fig. 19.--Odynerus Ovalis (Mag.)]
_Family 4, Eumenidæ._--One of the commonest and best-known species
belonging to this family is the Wall Wasp (_Odynerus parietum_), which
may be almost constantly seen haunting sunny walls during the months of
June and July. It makes its burrows in walls and high banks, while many
other allied species form their nests in the hollow stems of brambles.
_Family 5, Masaridæ._--This family contains the great bulk of the
solitary wasps, which, however, are principally inhabitants of warm
climates.
The _Masaridæ_ are a small group of black-yellow belted wasps,
which are found in the south of Europe, but not in Britain, two of
the commonest species being _Celonites apiformis_ and _Ceramius
fonscolombi_.
_Section 3.--Fossores._
[Illustration: Fig. 20.--Cerceris Capito.]
_Family 6, Philanthidæ._--Most of the species belonging to this family
are black with yellow spots and bands, and most of them are inhabitants
of the warmer parts of the earth. Some of the species provision their
nests with beetles and grasshoppers, while others attack bees, and are
very mischievous, destroying great numbers.
_Family 7, Crabronidæ._--This family includes a considerable number of
solitary species of wasps. In colour they are generally black spotted
and striped with yellow, but many of them are bright red.
The typical genus _Crabro_ is a very extensive one, including over 150
species, a great proportion of which are inhabitants of Europe, while
even Britain possesses more than thirty.
_Crabro cribrarius_ is the largest British species. Its food consists
principally of gnats and other dipterous insects. This insect and many
others burrow in the ground, generally in hard sandbanks. Another
species (_Crabro brevis_) frequents similar situations, and has been
known to provision its nest with small beetles.
[Illustration: Fig. 21.--Chlorion Viridiæneum.]
_Family 8, Nyssonidæ._--This family is not a numerous one comparatively.
_Mellinus arvensis_ is a black insect, about half an inch in length,
with stripes on the abdomen and yellow legs. It provisions its nest
with flies, and not being able to capture them by swiftness, runs past
them when they are resting in an unconcerned manner till they are
thrown off their guard, when they are pounced upon and carried off to
the nest.
_Family 9, Larridæ._--This family very much resembles the last. The
species are mostly small insects, few of them measuring half an inch in
length. They are usually black, sometimes with the abdomen red at the
base.
_Family 10, Sphegidæ._--Most of the insects included in this family
feed upon grasshoppers, and the manner in which they procure their
prey is very curious. In attacking their bulky prey they use every
endeavour to turn the grasshopper on its back. When they succeed in
this they inflict stings in different parts of the underside of the
abdomen and thorax, which soon paralyse the victim, which is then
dragged to the nest of the ruthless destroyer.
_Sphex flavipennis_ is a common species in the south of Europe.
_Family 11, Pompilidæ._--Most of the species of _Pompilus_ burrow in
sand or sandy soil, and store their nests with spiders and the _larvæ_
of insects.
One of our commonest species, _Pompilus fuscus_, is usually about
half an inch long, and is black, with the first three segments of the
abdomen red banded with black. This insect makes its appearance in the
spring, and may be observed in sandy places throughout the summer.
Another common British species is _Pompilus punctum_, which is black in
colour.
_Family 12, Bombicidæ._--This small family is not represented in
Britain, though found in southern Europe. Many of the insects burrow in
the sand, scratching a hole with their forefeet like a dog, as observed
by Sir S. Saunders in the Ionian Islands. In the daytime they may be
seen flying rapidly from flower to flower, and many of them exhale an
odour of roses.
[Illustration: Fig. 22.--Sapyya Clavicornis.]
_Family 13, Sapygidæ._--This is a small family containing only a single
genus, with very few species.
The species of _Sapyga_ occur in Europe and North America. They are
supposed to be parasitic in the nests of bees, but the females of the
common European species (_Sapyga pacca_) have been observed carrying
small caterpillars, from which Mr. Smith (the great authority on
Hymenoptera) justly infers that they are parasitic only to the extent
of usurping the burrows made in sandbanks and dead wood by more
industrious insects, their own structure not adapting them for the
labour of digging.
_Family 14, Scoliidæ._--Although this family is abundant in warm
climates, we have only two small species belonging to the genus
_Tiphia_ in Britain.
They are black, with more or less reddish legs, and measure from a
quarter to half an inch in length. In south Europe we meet with several
large and handsome species, one of which, _Scolia hortorum_, is black
with two yellow bands on the abdomen.
[Illustration: Fig. 23.--Scolia Hortorum.]
_Family 15, Thymidæ._--The insects of this family are almost
exclusively confined to Australia and South America, where they are
very numerous. They are generally of a black colour, with more or
less extended yellow markings. They are very stout insects; in fact,
their bloated bodies give them very little resemblance to any other
insects, except perhaps to the Oil Beetles. Very little has hitherto
been ascertained respecting their habits, but they are believed to be
parasitic.
[Illustration: Fig. 24.--Mutilla Maura (Male).]
_Family 16, Mutillidæ._--This family includes a large number of
species, probably 1,500, but from the differences presented by the
males and females, entomologists have found it difficult to arrive at
any certainty upon this point. The species are spread over all the
earth, but are particularly abundant in warm climates, where also, as
usual, they attain the largest size and the most beautiful colouring.
One of the best-known species in our own country is _Mutilla europæa_,
which is about half an inch long, of a black colour, hairy, with the
thorax entirely red in the wingless females.
[Illustration: Fig. 25.--Mutilla Maura (Female).]
This insect frequents the nests of Humble Bees, and its _larvæ_ appear
to be parasitic upon the _larvæ_ of the bees.
_Section 4.--Heterogyna._
_Family 17, Formicidæ._--To this family belongs the numerous species of
ants, which are social insects, organised after the fashion of the bees
and social wasps.
The number of species described is probably considerably over a
thousand, but the total number must be very much greater if Mr. Bates
is correct in his estimate that not less than 400 species inhabit the
valley of the Amazon.
[Illustration: Fig. 26.--Formica Lignipeda (Male). (Mag.)]
The habits of the ants are most interesting, and one of our greatest
living naturalists, Sir John Lubbock, has devoted much of his time in
elucidating their economy.
The nests are almost always chambered cavities, hollowed out either in
the ground, in walls, and similar situations, or in dead and decaying
wood.
One of the commonest examples in our own country is the Garden Ant
(_Formica nigra_), which may be found everywhere in gardens making its
nest in the ground.
Another common species is the pretty Turf Ant (_Formica flava_), which
generally haunts commons and heaths, casting up small hills, which
serve to throw off the rain; and this species in some localities makes
its nest under stones. The Wood Ant (_Formica lignipeda_) is another
familiar species.
[Illustration: Fig. 27.--Formica Lignipeda (Worker). (Mag.)]
A very large group of ants belong to the section _Myrmicinæ_, the
best-known species of which are the Red Ants, _Myrmica rubra_, and
their allies.
[Illustration: Fig. 28.--Myrmica Rubra (Male). (Mag.)]
A very minute species which has been introduced into this country,
probably from Brazil or the West Indies, is the Horse Ant (_Myrmica
molesta_). It is a very small brownish-yellow species, which seems
to have been first observed in England in 1828. It takes up its
abode in houses, frequently in the neighbourhood of the kitchen
fireplace, and when it multiplies becomes such a pest as to render
the house uninhabitable. Some of the metropolitan districts have been
particularly infested.