natural history. 
241 
creature ; which appears healthy, and even 
foixietiiiies transforms itfelf to a chryfali . , 
It is, not uncommon to lee caterpillars fixed 
upon trees, as if they were fitting upon 
their eggs ; and it is afterwards dilcovered 
that the larvx, which were within their bo* 
dies, have Ipun their threads, with which, 
as with cords, the caterpillars are faltened 
down, and fo perifli miferably. 
The ichneumons performed fpecial fervicc 
in the years 1731 and 1732, by multiplying 
in the fame proportion as did the caterpillars : 
their larvte dedroyed more of them than 
could be efleded by human indufli y._ Thole 
larvte, when on the point of turning into 
chryfalids, fpin a filky cod. Nothing is 
more furprifing and fmgular, than to lee 
thofe cods leap, when placed on the table, or 
hand. Plant-lice, the larvae of the curcu- 
liones, fpider’s eggs, are alio lometimes the 
cradle of the ichneumon-fly. Carcafes of 
plant-lice, void of motion, are often fouml 
on rofe-tree leaves. They are the habita- 
tion of a fmall larva ; which, after having 
eaten up the entrails, deilroys the (prings and 
inward economy ol the plant-loufe, performs 
its metamorphofis under (helter of the pel- 
licule which enfolded it, contrives itfelf a 
fmall circular outlet, and falhes forth into 
the open air. 
There are ichneumons in the woods, 
which dare attack fpideV'', run them through 
with their fUng, tear them to pieces, and 
X thiH 
