344 
THE STUDY OF INSECTS . 
size, some of them being nearly as large as the largest of our 
moths. The most obvious character limiting this family is 
the structure of the antennae of the male. These agree with 
those of the Saturniidae in having two pairs of teeth to each 
segment, but differ in being pectinated for only a little more 
than half their length. These moths also differ from most 
Saturniidae in having two anal veins in the hind wings. Al¬ 
though the antennae of the male are broadly pectinated, 
those of the female are filiform. The palpi and maxillae are 
very small. The thorax and abdomen are densely clothed 
with long hairs. The wings are strong, with prominent veins. 
The frenulum is wanting, and the humeral angle of the hind 
wings is very largely developed. In the fore wings vein V, 
arises from the discal vein (Figs. 422, 423). 
The larvae are armed with horns or spines, of which 
those on the second thoracic segment, and sometimes also 
