894 
LEPIDOPTERA. 
the elm, and, according to Mr. Abbot, on the dogwood or 
cornel, and the sassafras ; they feed well also on the leaves 
of clover and* Indian corn. They are of a pea-green color, 
with a broad brown stripe edged below with white on each 
side of the body, beginning on the fourth ring and ending 
at the tail; they are covered with spreading clusters of 
green prickles, tipped with black, and of a uniform length ; 
each of these clusters consists of about thirty prickles branch- 
ino; from a common centre, and there are six clusters on 
each of the rings except the last two, on which there are 
only five, and on the first four rings, on each of which there 
is an additional cluster low down on each side ; the feet 
are brown, and there is a triangular brown spot on the 
under side of each ring, beginning with the fourth. The 
prickles are exceedingly sharp, sting very severely when 
the insect is handled, and produce the same kind of irrita¬ 
tion as those of the nettle. When young these caterpillars 
keep together in little swarms. They do not spin a common 
web, but, when not eating, they creep under a leaf, where 
they cluster side by side. In going from or returning to 
their place of shelter they move in regular files, like the 
processionary caterpillars QLasiocampa processionea) of Eu¬ 
rope, a single caterpillar taking the lead, and followed closely 
by perhaps one or two in single file, after which come two, 
side by side, close upon, the heels of these creep three more, 
the next rank consists of four, and so on, the ranks contin¬ 
ually Avidening behind, like a flock of Avild geese on the 
Aving, but in perfectly regular order. When about half 
groAvn they disperse, and each one shirks for himself. At 
the age of eight Aveeks they get .to their full size, in the 
meanwhile moulting their skins four times, and finally meas¬ 
ure tAvo inches and a half or more in leno-th. At this a^e 
they leaA^e off eating, crawl to the ground, and get under 
leaves or rubbish, which they draAV round their bodies to 
form an outer covering, within Avhich they make an irregular 
and thin cocoon (Fig. 189), of veiy gummy brown silk, 
