STATE AGRICULTURAL SOCIETY. 
835 
LOCUST. LEAVES. 
posteriorly, with a darker green streak along its middle ; passing its pupa 
state in the leaf, which falls to the ground, and the following June gives 
out a minute moth 0.45 wide across its spread wings, which are blackish 
brown on their outer half, tawny yellow on their inner side, and marked 
with an oblique white band before the middle, a broad grayish white band 
or large triangular spot on the middle, and half way from this to the tip a 
white spot on the outer and a pale rose red one opposite it on the inner 
margin, and also a small white spot on the tip and on the base. 
Of the seventeen small leaves or leafets which commonly form each com¬ 
pound leaf of the locust, usually two or three, and frequently double that 
number, show these white blisters on their under sides. And it is not rare 
to see two or three of them upon the same leafct, which usually turns 
yellow and drops prematurely from the tree, when thus severely invaded. 
But where it has only one insect preying upon it, it usually remains green 
and survives the attack. For of the two layers of parenchyma in the 
leaves, it is only the lower that is ate by these worms, the upper one being 
left entire, whereby the upper surface of the leaf remains green, or is but 
slightly discolored with a yellowish cloud at this place. The white sep¬ 
arated skin of the under surface is very thin and delicate, so much so that 
frequently the worm may be perceived beneath it, sometimes feeding at the 
outer edge of the spot, but more commonly at rest towards its centre, or 
turning its head with a sudden spiteful jerk, first to one side and then to 
the other, being evidently aware that it is interfered with, and resorting to 
this motion to frighten away the intruder. And not unfrequently two 
worms are seen occupying the same cavity. 
The Larva when young and as found in the smaller spots, is of a very palo green or white 
color with a darker green or a pale brown streak along its middle. It is very much flattened, 
and is broadest anteriorly across its neck, gradually tapering from thence to the tip. It is 
divided into thirteen segments by deep transverse constrictions, giving it a serrated appear¬ 
ance along each side, and from the tip of each of the projecting teeth arises a short white 
hair. When full grown it measures 0.18 in length and then presents a somewhat different 
aspect, the middle of the body being now as broad or slightly broader than the anterior end, 
with the sutures more doeply impressed, and the projecting teeth along each side arc rounded 
and not so angular at their ends as before, and are of a yellow color, at least those at each 
end. And now small retractile legs are perceptible, enabling the worm to move about with 
more facility than when it was young. There are three pairs of small conical watery-white 
legs placed on the three thoracic segments, and on the third, fourth and fifth abdominal seg¬ 
ments is a pair of minute pro-legs, scarcely to be discerned except whon the worm is crawling. 
The pupa lies in a small, broad, oval cocoon, 0.18 long, and 0.12 thick, 
woven of exceedingly fine white silk, through the sides of which the insect 
within is scon, of a pale yellowish color. This cocoon is suspended near 
the centre of the cavity, by a few threads of fine silk, crossing irregularly 
in different directions; the cavity in the leaf having now become much 
more deep and spacious than when it was first mined by the worm. The 
manner in which nature has so adjusted her work, here, as to cause this 
cavity to grow more deep and roomy, is truly curious. We have already 
stated that it is only the lower layer of the parenchyma of the leaf on 
