Alderson: Notes on Chrysopa perla and C. flava. 85 
them in a small tin box with a glass lid, it was most interesting 
to watch them hunt their prey. They seemed most voracious 
little creatures, and would move restlessly about at a great 
pace until they met with an aphis. They did not appear to be 
guided by sight in finding food, but rather by sense of feeling. 
When they came across an aphis they would strike with great 
rapidity, fixing their sucking spears into the body of the un- 
fortunate victim, which never, so far as I could see, would offer 
the slightest resistance. It was a wonderful sight to see the 
subsequent proceedings. Both insects would remain perfectly 
still, and by the aid of an ordinary lens it was quite possible to 
see the vital juices of the aphis pass through the sucking spears 
into the body of the Chrysopa, until in a very short time the one 
became an empty sack of skin and the other a full-fed gour- 
mand. After a short rest the same process would be repeated, 
many times a day, and also during the night, for I frequently 
found the larvee still feeding when I looked at them after dark. 
I think it probable, too, that they sometimes mistook one 
another for aphides, as their numbers certainly decreased, and 
they seemed to have little powers of discrimination. In the 
case of C. flava, one larva was actually seen devouring a 
larva of Dictyopleryx bergmanniana, which had been introduced 
with the rose leaves. The larvae became much more sluggish 
as they grew older, probably owing to their increased bulk, as 
they grew with great rapidity. 
The following is a rough description at seven days old :— 
Head.—Pale greenish, with three characteristic jet-black 
marks. 
Antenne.—Madder brown. 
Sucking Spears.—Pale madder brown ; darker at the tips. 
Eyes.—Jet-black. 
Thorax.—Whitish green at sides and beneath, brown 
madder above; two rather crescent-shaped marks at sides, jet 
black. 
A black dividing line runs all down the centre of the back, 
and on each segment are placed four warts (two larger and two 
smaller), two on each side of the dividing line. 
The thoracic warts are black, and the /arger ones are placed 
nearer to the central line. 
The abdominal warts are whitish grcen, and the positions are 
reversed, the smaller one being placed next to the dividing line. 
The underneath parts of the larve are whitish green, with 
two madder lines running down the abdomen. 
1907 March x. 
