Why is the study of insects a source of perpetual variety?
Because the localities of insects are, to a certain extent, constantly changing. Insects, also, which are plentiful one year, frequently become scarce, or disappear altogether the next – a fact, strikingly illustrated by the uncommon abundance in 1826 and 1827, of the seven-spot lady-bird in the vicinity of London, though during the two preceding summers, this insect was comparatively scarce, while the small two-spot lady-bird was plentiful. – J. Rennie.
