Easily within range

E.L. Grant Watson, What to look for in summer, Ill. C. F. Tunnicliffe, Loughborough, Will & Hepworth, 1960, p.12.

The caddisfly larvae, in contrast to the water-scorpions, usually live in freshwater streams. Their protective cases, are made of materials that come easily within range- littele bits of sticks and tiny shells. These coverings disguise them from enemies and from their intended prey.