PERIDIvOMIA ARETHUSA. 
PLATE XVIII. Fig. 1, Fem. 
This genus lias lately been proposed for the recep- 
tion of a few species formerly classed among the 
Nymphales. They are re- 
markable for having the 
surface covered with blue 
markings on a dark 
ground, and in other re- 
spects seem to be entitled 
to generic distinction. 
The neuration of the 
wings presents the an- 
nexed arrangement. — 
The caterpillar (at least 
of P. Amphimome) bears 
some resemblance to that 
of Morpho. It is long 
and attenuated behind, 
the anal extremity deeply 
forked, and the head armed with eight strong 
unequal spines, resembling a kind of coronet. The 
chrysalis is elongated, bifid anteriorly, and having a 
series of dorsal spines. They are natives of the New 
