The subfulcate primaries ally this group to the Platypteryginœ, and a certain vague resemblance to the Geometridœ may be found in the tendency which the upper surfaces of the wings show to display the same pattern on both wings. The ocelli are absent, the oral structure undeveloped, the hind wings are without frenulum. The species form mostly large cocoons, and the characteristics of the family are pronounced in this sub-family of silk-spinners. The male antennæ are feathered to the tips, each joint bearing a double pectination.