The irritation set up by the hatching egg and its resulting larva appears to be the stimulus to development, and net a poison or enzyme injected by the insect.
A full-grown larva digs a pit about 2 in.
The beetles are fierce Antenna of Larva of Gyrinus.
The larva pierces the vessels of the plant with sharp processes at the hinder end of its body.
Extremes we find various transitional forms: an active larva, as described above, but with four-segmented, single-clawed legs, as among the rove-beetles and their allies; the body well armoured, but slender and worm-like, with very short legs as in wireworms and mealworms (figs.