State Agricultural Society. 
925 
THEIR GROWTH. CAST SKINS. LARVA DESCRIBED. 
leaf and leaving only the veins. They drop a multitude of little 
black grains upon the leaves below them, which enable us fre¬ 
quently to discover broods of these worms which would otherwise 
escape our search. 
When one leaf is consumed they migrate to another. And as 
they increase in size, so often as their skins become uncomfortably 
tight, they cast them off and come out in a new dress. These evacu¬ 
ated skins are frequently seen, having their tips hooked around a 
leaf-stalk or the margin of a leaf, with the head end hanging down- 
ward, looking as though the worm in wriggling out of it had drop¬ 
ped itself to the ground. They are a shrivelled and distorted mass, 
the skin being of a flesh-red color wherever it is seen in the inter¬ 
stices between the shining black warts, which occupy most of the 
surface, the black bristles and black anterior legs projecting out in 
every direction—the black, shining head, similarly bristled, appear¬ 
ing at one end of the mass, split asunder into two segments. 
As they increase in size they become more voracious, and were a 
whole brood to continue together, one leaf would not suffice to feed 
them an hour. They, therefore, separate, and as they approach 
maturity become more subdivided and scattered around the spot 
which they occupy, until commonly only one, two or three are 
found on a leaf, which they commence eating at its tip, consuming 
it more and more as they progress towards its base. They con¬ 
tinue to increase in size with each successive change of their skins, 
until they attain three-fourths of an inch in length. 
The Larva when nearly or quite mature is about six times as long as thick, and 
of a cylindrical form, very slightly tapering towards its tip, which is usually held 
in a curved position, either downward, upward, or to one side. It is shining and 
greasy-looking, of a pale bluish green color with the neck and the segment next 
to the last pale greenish yellow. It is ornamented with numerous elevated pol¬ 
ished black dots, each one of which gives out a short black bristle. These dots 
arc symmetrically placed in rows running both lengthwise and crosswise of the 
body, there being along the back twenty-four dots in each row. Each abdominal 
segment has three transverse rows, with four dots in the first, six in the second 
and ten in the third, with an additional dot between the lower ends of the second 
and third rows, and another much larger one below the ends of the first and second 
rows, this last dot having two others below it, on the base of the prolegs. On tho 
thoracic segments the dots are fewer in number and differently arranged. The 
extreme tip of the body is tinged with yellow, with a black spot on its upper side, 
and two short horn-like processes. The head is .black, highly polished and stud¬ 
ded over with bristles. On the underside are three pairs of true legs, anteriorly, 
on the breast, which taper to a sharp point and are black and shining. With 
these the larva clings to the leaf when it is feeding. They occupy the three first 
