IL cONFINED IN STAGNANT AIR. 7% 
from nine webs: from two, there came none. 
On examining the fterile webs, 1 found the cater- 
pillar transformed to a chryfalis ; but the butter- 
fly did not come out, as it died while in this 
ftate. The webs of the eleven caterpillars in this 
clofe veffel were of good filk; and their only 
difference from others -was in not being fo hard 
and elaftic as cocons generally are. 
Other caterpillars, efpecially thofe of the elm 
and oak, underwent changes fimilar to the filk- 
worms in clofe veffels. The fame method was 
adopted of confining them in veffels where the 
lower extremities of branches had been immer- 
fed in water. - 
The metamorphofes of the larve of large 
flefh flies were more diftinétly feen. I put a piece 
of flefh nearly putrid at the bottom of one of the 
weflels : it ferved them for food nine days, that 
is, all the time they were worms, and until they 
became nymphs. We know, that when their 
change approaches, they abandon the putrid flefh, 
and, feeking a dry fituation, moft commonly 
conceal themfelves under an arid dufty earth. 
Thofe confined likewife abandoned the flefh, tra- 
verfed the veflel, and were in conftant motion 
more than halfa day. Their anxiety to efcape 
was evident ; but, unable to effeé it, they retired 
to the fides at the extremity of the neck of the 
veffel, which was almoft parallel with the floor, and 
oar became 
