BUGS. 173
sexual dimorphism, such as Systellonotus (Capsidae), in which
the female resembles an ant, but the male is a typical Capsid ;
in Microphysa and Myrmedobia (Cimicidae) the males are typical
Anthocorids, whilst the females are mostly brachypterous, and,
looked at from above, remind one of some of the old wine flagons
with large bodies and small necks. The females of Mecomma
ambulans and Byrsoptera caricis are pear-shaped and
brachypterous, whilst the males are typical Capsids.
The majority of Bugs are inconspicuously or protectively
coloured (i.e., they more or less resemble their environment,
many being green or brown), and most of them are of a retiring
disposition, dodging deftly beneath leaves or flowers on the
approach of danger. Amongst the Pentatomidae and Coreidae,
on the other hand, there are not a few very conspicuously coloured,
and some at least of these are amongst the largest and most
noisome of the group. No doubt there is some connection
between these characteristics, but the connection does not
apply in all cases, for that brilliant scarlet species, Pyrrhocoris
apterus, is exceedingly conspicuous and takes no trouble to get
under cover ; yet it is said to be palatable to a large number
of birds and to emit no disagreeable smell. Cases of mimicry
appear to be uncommon and to be confined to a few species (such
as Pilophorus clavatus) which, besides those already mentioned,
resemble ants, but the exact object of this resemblance has not
yet been certainly determined.
The economic importance of bugs is probably limited, so far
as this country is concerned, to some half-dozen species. Chief
amongst these is, of course, the Bug, but although held in dis-
repute, Cimex lectularius is by no means unenterprising and it
can run with unexpected quickness. Its aptitude at concealing
itself in the smallest crevice is of world-wide reputation, and
is the outcome of its astonishing flatness. Next to this, probably
the most interesting feature of its anatomy is its thorax, which
is almost crescentic, a shape common to the genus. Time is
too short now to touch upon its life history, beyond mentioning
that, like the dog, the cat, and other domestic animals, and the
house sparrow, it is almost invariably found only in association
with man and his works ; but it is said to occur rarely under the
bark of trees and to be able to live on such things as paste and
the sap of soft fresh wood, thus being independent of animal
blood.