scribe a definite line of boundary. The characteristic peculiarity of the Arctiidæ, however, is, that they have the wings deflexed in repose, the posterior pair not extending beyond the costa of the anterior, and they are connected together by an apparatus consisting of a kind of ring in the one which receives an elastic spine from the other, thus forming a connexion, but still admitting of considerable independent motion. The antennæ are bipectinated, sometimes serrated; palpi rather small, mostly triarticulate; spiral tongue generally short, and sometimes altogether wanting. The caterpillars of the more typical species are densely clothed with hairs; sometimes with long fascicles or tufts of peculiarly formed hairs; and in some cases they are naked. They feed externally on plants.
This family corresponds to the Faux-Bombyx (Pseudo-Bombyces) of Latreille. It comprehends a great number of species, many of which are conspicuous from their rich colouring, but they never make any approach to the size of the gigantic Bombycidæ.
