STATE AGRICULTURAL SOCIETY. 
353 
PEAR. TRUNK. 
The bark of this limb was covered with an exceedingly thin 
gray film, appearing as though it had been coated over with var¬ 
nish, which had dried and cracked and was peeling off in small 
irregular flakes, forming a kind of scurf or dandruff upon the 
bark. In places this pellicle was more thick and firm and ele¬ 
vated into little blister-like spots of a white color and waxy 
appearance, of a circular or broad oval form, less than the tenth 
of an inch in diameter, abruptly drawn out into a little point at 
one end, which point was stained of a pale yellowish color and 
commonly turned more or less to one side. On breaking open 
any of these spots with the point of a needle, quite a number of 
exceedingly minute oval eggs of a glossy bright purple color were 
found beneath. These eggs probably produce mites of such 
minute size as to be wholly imperceptible to the naked eye, 
myriads of which, there is little doubt, at times overrun the bark 
of particular trees of this kind, exhausting their juices and 
causing them to pine and droop, when the proprietor is wholly 
unable to discover the occasion of their unthriftiness. The habits 
and changes of this insect will be similar to those of the Apple 
bark-louse, (No. 15) and other kindred species. It is probably 
this species as it appears in autumn, of which, as this page is pass¬ 
ing through the press, I notice some valuable observations by A. 
0. Moore, in the American Agriculturist, vol. xvi., p. 287. 
55. Pear-tree Psylla, PsyUa Pyri, Linn. (Ilomoptcra. Psyllidaa.) 
The smaller limbs and twigs drooping, their bark rusty black¬ 
ish, and a multitude of ants and flies gathering around them to 
feed on the honey dew which is dropped copiously by a small 
yellow jumping insect resembling a louse, which punctures the 
bark and sucks its juices, frequently killing the tree. After the 
middle of summer appearing with transparent wings, and its head 
deeply notched in front, its color now being orange yellow with 
the abdomen greenish. Length 0.10. See Harris’s Treatise, p. 
202 . 
<><*• Pear blight beetle, Scolytus Pyri, Peck. (Coleoptera. Scolytidoe.) 
Particular twigs of the pear, apple, plum and apricot suddenly 
Withering and dying in the middle of the summer; small perfo- 
[Ag. Trans.] 
W 
