larity for this purpose in rows, and at first devour 
only the upper pellicle and the green parenchyma 
of the leaves, and in the evening retire to their 
web. In about three weeks they cast their skin, 
and afterwards proceed to feed as before, enlarg- 
ing their web from time to time, and forming it 
on all sides as strong and secure as possible. In 
this thev remain the whole winter in a state of 
torpidity, ^till being enlivened by the warmth of 
the returning spring, they again issue from their 
covering, and being now grown stronger, begin 
to devour the whole substance of the leaves, in- 
stead of contenting themselves with the upper 
]iart as in their very young state. The destruc- 
tion which they sometimes cause to the verdure 
of the country may be judged of by their ravages 
in the year 1782, when, according to the account 
of the ingenious Air. Curtis, author of the Flora 
Londinensis, &c. in many parishes about London 
subscriptions were opened and the poor people 
employed to cut off and collect the webs at one 
shilling per bushel, which were burned, under the 
inspection of the church-wardens, overseers, or 
beadles of the respective parishes. At the first 
onset of this business Mr. Curtis assures us he 
was informed that fourscore bushels were collected 
in one day in the parish of Clapham alone. When 
these caterpillars are arrived at full growth, which 
is usually about the beginning of June, each 
spins itself a separate web, in which it changes to 
a dark-brown chrysalis, out of which in the begin- 
uing of July proceeds the Aloth. 
