STATE AGRICULTURAL SOCIETY. 
801 
OAK. LIHB3. 
it has acquired sufficient strength to sever the woody fibres. It then 
passes transversely around the limb beneath the bark, girdling it by cut¬ 
ting off all the %ofter outer fibers and leaving the harder ones in the 
middle of the limb uncut, whereby the limb is sustained until the wind 
strikes it. How surprising that these little creatures have such intelli¬ 
gence given them as enables them to vary their operations to such an 
extent, according to the circumstances of their situation in each particu¬ 
lar case! I should be inclined to think the beech pruner a different 
species from that of the oak, as it dwells beneath the bark instead of in a 
lateral twig, and cuts off the outer instead of the inner wood of the limb; 
but the worm is identical with that of the oak in its external appearance, 
and one of these worms which I placed in a cage, falling from its fractured 
burrow in the beech limb, forsook this wood and commenced boring* into 
an oak limb lying beside it. 
Not only the limbs but small young trees, at least of the white oak, are 
sometimes felled by these insects; in which cases the worm, instead of 
cutting the wood off transversely, severs it in a slanting or oblique direc¬ 
tion, as though it were aware the winds would prostrate a perpendicular 
shoot more readily by its being cut in this manner. 
The LAitva grows to a length of 0.60, and is then 0.15 thick across its nock, whore it is 
broadest. It tapers slightly from its neck backwards, the hind part of its body being nearly 
cylindrical. Is is a soft or fleshy grub, soinowlmt shining and of a white color, often 
slightly tinged with yellow, its head, which is small and retracted into the neck, being black 
in front. It is divided into twelvo rings by very deep, wide, transverso grooves. The neck 
or first ring is much the largest, and shows two very pale tawny yellow bands on its upper 
Bide, the anterior one slightly broken asunder in its middle, and on each side beyond the ends 
of theso bands is a spot of tho same color. Tho two or three rings next to the neok are 
shorter than the others, and leas widely separated from each other. A faint stripe of a 
darker color may be discerned along the middle of tho baok, widely broken apait at each of 
the sutures. The last ring is much narrower and more shining than tho others, and is out 
across by a fine transverse line, dividing it into two parts, of which the hinder one or tip is 
bearded with small blackish hairs, and a few fine hairs are perceptible upon the other rings. 
The two last rings are retracted into tho ring which precedes them, at the pleasure of tho 
animal, whereby this ring becomes humped and swollen; and it appears to bo chiefly by thus 
enlarging the end of its body that the worm holds and moves itself about in its coll, its feet 
being so weak and minute that they are scarcely poroeptiblo and can bo of little service. It 
has three pairs of soft conical jointed feet, resembling its antenna) in their size and sliapo. 
The first pair is placed on an elevated wrinkle of the skin in tho suturo between the first and 
second segments of the thorax, more distant from each other than aro those of the second and 
third pairs, which are situated on the rniddlo of the elevation of the second and third segments. 
Some of the worms euter their pupa state the last of autumn, and others 
not till the following spring. Hence in examining the fallen limbs in the 
winter, a larva may be fouud in one, a pupa in another. Preparatory to 
entering its pupa state, the larva places a small wad of woody fibres, 
sometimes intermingled with worm-dust, below it, in its burrow, and 
sometimes another wad above it if the burrow runs far up the limb, thus 
partitioning off a room one or two inches in length in which to lie during 
its pupa state. The shrivelled cast skin of the larva will be found at 
the upper end of this cell, after it has changed to a pupa. 
[Ac. Trans.] 31 
