234 DISEASES OF INSECTS. 
large beetles, where do they take their principal growth ? 
It cannot be as parasites on the little bees or flies that 
they are usually found upon ; they must soon desert 
them, and like their kindred blister-beetles, as is most 
probable, have recourse to vegetable food. What an 
anomaly in rerum natwra ! It is much to be wished that 
some skilful insect-anatomist would carefully dissect the 
Meloe i or perhaps by digging round the roots of the 
ranunculuses and other acrid plants the larva of that 
beetle might be discovered in a later stage of growth, 
and so this mystery be cleared up. I should observe 
here, that Scopoli has described three parasites as Pedi- 
cnli ; viz. P. rostratus, coccincus, and Cerambycinus ; the 
first of which Fabricius has adopted under the name of 
P. Gryllotalpa, but which are all evidently hexapod 
Acarina a . 
Acariasis seems a disease almost as universal amongst 
insects as Scolechiasis ; with this difference however, that 
Acari most commonly take their station upon them in 
their perfect state. You have doubtless often observed 
the common dung-beetles (Geotrupes) covered on the 
underside of their body with small mites (Gamasus 
Colcoptratorum) which look as if they were engaged 
in suction — they are often so numerous that no part is 
uncovered; they also attack other beetles 15 , and are some- 
times found on humble-bees. They are easily disturbed, 
run with great swiftness, and may often be seen in hot- 
beds and fermenting dung prowling in search of the 
stercorarious beetles. But the most remarkable insect 
of this kind is the Uropoda vegetans : it derives its nu- 
triment from the insects it assails not by its mouth, but 
» Ent. Cam. 1052—4. b Histcr particularly. 
