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Thus refted the matter for that time; but my  curiofity being 
roufed by the ftrangenefs of the incident, I examined large maffes 
of ftone, wherever I faw them, this laft year ; and happening to be in 
Buckinghamfhire in July, I found the whole. myftery explained. 
Several large ftones that ftood in water at their bottom, tho’ 
dry enough above, were covered with: grey, ftony tubules of this 
kind ; and about one of thefe maffes, on the evening of the 18th of 
July, I found more than fifty, of the Fly, to the Worm of which 
they owed their origin. °Tis a very pretty creature, and in all 
refpects of the Day-Fly kind. 
Its Heap is hoary, and of a ftrong fine green, with a black round 
{pot on its centre, fhining at the fummit. 
The Eyes are black as jet. 2 
The Studs are brown. 
The Antlers are fcarlet, long, thruft trait forward, and ufually crofs’d. 
The Mouth is dufky. 
Its TRUNK is of a lovely green, and is join’d to the body by a kind 
of neck, which is alfo of a velvety green. ; 
The Back is beautifully variegated with ftreaks and dots of gold. 
The Scutcheon is of a lighter green. 
Its Bopy is thick, and green, and is connected to the Trunk almoft 
' without a divifion. 
Its Lecs are of a pale brown. 
Its Wincs of the fame pearly grey with the preceding; but ele- 
gantly vein’d, and clouded with a pale blue, and a light brown. 
The BrisTLeEs are amber-colour. 
I believe this Fly lives no longer than one evening in its wing’d 
ftate: the Females, among thofe I faw, were very bufily depofiting 
eggs in all the cracks and crevices of the ftones. The Worms 
hatched from thefe,. make the ftone tubules for themfelves, and pro- 
bably live in them one or two years, 
INS EC Ts. 
