26 MODERN ARRANGEMENT OF 
Trise I1T.—NOCTURNA. 
All the wings are horizontal or inclined in repose ; 
the antennee are setaceous. 
With the exception of a small number, the lower wings in 
this tribe are furnished with a bridle, formed by a strong and 
sharp horny bristle, or a bundle of setw adapted to a groove in 
the upper wings, and keeping them horizontal when at rest. 
The chrysalis is almost always inclosed in a cocoon rounded 
before, or without angles. The number of membranaceous feet 
varies in the caterpillar. 
Famity I.—Bompycrres, Latreille. 
The antenne are pectinated or serrated, at least 
in the males; the trunk spiral and very short, 
or almost none; body generally woolly and 
thick in the females ; wings often extended, and 
when they are inclined, the lower ones margin 
the other two, or are turned up ; caterpillars pro- 
vided with sixteen feet. 
1. Wings broad, either extended or inclined like a roof, the 
lower ones in this case bordering the upper ; caterpillars liy- 
ing exposed, on leaves. 
The genera are Arracus, Lastocampus, and Bompyx. 
II. Wings oblong, narrow, always inclined, the lower ones en- 
tirely covered ; caterpillars living in the interior of vegetables, 
or concealed in the earth and gnawing their roots. 
This section has but one genus, Heprazus. 
Genus Bomsyx, Fabricius. 
The wings are entire, horizontally extended or in- 
