In‐du″sial (?), a. [See Indusium.] Of, pertaining to, or containing, the petrified cases of the larvæ of certain insects.
Indusial limestone(Geol.), a fresh-water limestone, largely composed of the agglomerated cases of caddice worms, or larvæ of caddice flies (Phryganea). It is found in Miocene strata of Auvergne, France, and some other localities.