135 
pale yellowish patch on its inner side; third line yellow¬ 
ish and indented, central spot black. The antennae are 
pectinated. 
Localities for this species are London and Chelsea. 
The situations where it is found are buildings in which 
there is old timber. 
The perfect insect appears in June. 
The caterpillar is dull blackish, with raised reddish 
spots covered with bristles. 
The date of the appearance of the caterpillar is in July. 
It feeds on the lichens and fungi which grow on de¬ 
cayed wood. 
The chrysalis is found under the ground. 
GEOMETRIDiE. 
PSEUDOPTERPNA CYTISARIA. 
GRASS EMERALD. 
Plate XXI. Figure 10. 
This insect measures from an inch and a quarter to 
nearly one inch and three quarters in expanse. 
Male: paledullgreen; the first line dark greenish-grey, 
nearly straight across, but somewhat waved; second 
line also dark greenish-grey, indented and bent; third line 
whitish, but sometimes hardly visible ; central spot dull 
green, but very indistinct. Hind wings paler dull green, 
crossed with a whitish line behind a darker one, following 
some way within the outer margin. The antennas are 
slightly pectinated. 
