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THE ESSEX NATURALIST.
From this it will be seen that the Aculeates are comprised in
the last three sections. They may be divided into "Solitary,"
"Colonial," "Social," and "Cuckoo" species, which terms may
be explained as follows :—
"Solitary" means that the female bee or wasp prepares and
stocks her "nest" independently of other individuals and dies
without seeing her offspring, who mature individually without
any intercourse with their mother or each other. "Colonial"
means that, although strictly solitary in their economy as
individuals, the females of this class establish their "nests" in
more or less close proximity to those of others of their own kind.
"Social" means that the female, after starting her nest, rears
the first few offspring herself and afterwards continues with
them and the subsequently reared young—the latter taking over
all the duties of the colony except the laying of fertile eggs—all
living together as one family. It will thus be seen that these terms,
Solitary, Colonial and Social, are not to be understood here in
the sense in which they are usually applied to humanity ; for
the "Solitary" species are in no sense hermits, the "Colonial"
species hold no direct intercourse with one another, and "Social"
is not exactly applicable to the members of a human family.
The "Cuckoos," as their name implies, are those which lay their
eggs in the nests of hosts, the "cuckoo's" offspring devouring
either the host's offspring or the food provided for it, or both.
In general, the result is that the host offspring dies, but cases
are on record in which perfect specimens of both host and cuckoo
have emerged from the same cell ; in such cases, of course, the
food provided must have been sufficient for both.
The Solitary bees and wasps of Britain are all winged in the
perfect state, and the males are usually smaller and more slimly
built than the females ; but on the other hand they are more
numerous and much more active. Where there is a normal
eccentricity of structure, such as an unusually large head, it is
generally confined to the males, but the females often exhibit
excess of colouration.
The life histories of these insects seem to be modelled on a
broadly uniform plan. Most of the females burrow in the ground,
especially in sandy soils, or in old trees, bramble sticks, walls,
etc., or they adopt for nesting purposes suitable cavities
already made, such as empty snail-shells, locks and keyholes.