INSECTS AND VERMES. 
347 
whole forests and districts. At this season they leave their 
aurelia, and issue forth in their fly state^ swarming and 
covering the trees and hedges. 
In a field at Greatham^ I saw a flight of swifts busied in 
catching their prey near the ground ; and found they were 
hawking after these Phalcena. The aurelia of this moth is 
shining and black as jet ; and lies wrapped up in a leaf of 
the tree, which is rolled round it, and secured at the ends 
by a web, to prevent the maggot from falling out.^ 
EPHEMERA CAUDA TRIESTA — MAY FLY. 
June 10/1771. Myriads of May flies appear for the first 
time on the Alresford stream. The air was crowded with 
them, and the surface of the water covered. Large trouts 
sucked them in as they lay struggling on the surface of the 
stream, unable to rise till their wings were dried. 
This appearance reconciled me in some measure to the 
wonderful account that Scopoli gives of the quantities emerg' 
ing from the rivers of Carniola. Their motions are very 
peculiar, up and down for many yards almost in a perpendi- 
cular line.^ 
SPHINX OCELLATA, 
A VAST insect appears after it is dusk, flying with a humming 
noise, and inserting its tongue into the bloom of the honey- 
^ I suspect that the insect here meant is not the Phalcena quercuSy 
but the Phalcena viridata, concerning which, I find the following note 
in my "Naturalist's Calendar" for the year 1785 : — 
About this time, and for a few days last past, I observed the leaves 
of almost all the oak trees in Denn Copse to be eaten and destroyed, 
and, on examining more narrowly, saw an infinite number of small 
beautiful pale green moths flying about the trees ; the leaves of which 
that were not quite destroyed were curled up, and withinside were the 
exuvice or remains of the chrysalis, from whence I suppose the moths 
had issued, and whose caterpillar had eaten the leaves. — Markwick. 
2 I once saw a swarm of these insects playing up and down over the 
surface of a pond in Denn Park, exactly in the manner described by 
this accurate naturalist. It was late in the evening of a warm summer's 
day when I observed them. — Markwick. 
