1838. HOUSE— No. 72. 87 



bottom of its burrow, makes its escape from the tree in the latter 

 part of June, or beginning of July, and probably deposites its eggs 

 before August has passed. This little beetle, which is only one- 

 tenth of an inch in length, was named Scolytus Pyri^ by Prof. Peck ; 

 it is of a deep brown color, with the antennae and legs rather paler, 

 or of the color of iron-rust. The minuteness of the insect, the dif- 

 ficulty attending the discovery of the precise seat of its operations 

 before it has left the tree, and the small size of the aperture through 

 which it makes its escape from the limb, are probably the reasons 

 why it has eluded the researches of those persons who disbelieve in 

 its existence as the cause of the blasting of the limbs of the pear- 

 tree. It is to be sought for at or near the lowest part of the diseas- 

 ed limbs, and in the immediate vicinity of the buds situated about 

 that part. The remedy, suggested by Mr. Lowell and Prof. Peck, 

 to prevent other limbs and trees from being subsequently attacked in 

 the same way, consists in cutting off the blasted liinb below the seat 

 of injury, and burning it before the perfect insect has made its es- 

 cape. It will therefore be necessary, carefully to examine our pear- 

 trees daily, during the month of June, and watch for the first indi- 

 cation of disease, or the remedy may be applied too late to prevent 

 the dispersion of the insects among other trees 



In examining the leading shoot of the white pine. Prof. Peck 

 found another insect which he called Scolytus strobi. Half a dozen 

 were obtained from the terminal bud. This insect is exceedingly 

 minute, being only six hundredths of an inch in length, and two hun- 

 dredths of an inch in diameter. It is black and polished, the feet are 

 pale brown, and the antennae dusky. The wing-cases have longitu- 

 dinal rows of short bristles, the thorax is densely covered with 

 shorter ones, and is rough in front with minute tubercles. 



In the genus Bostrichus, the body is cylindrical, the thorax glo- 

 bose, generally rough with tubercles, the elytra or wing-cases are 

 arched so as to cover nearly two-thirds of the body, are often ob- 

 liquely truncated or cut off behind, and armed with teeth at the 

 apex ; the antennae are terminated by a pectinated or serrated club. 

 Bostrichus basillaris, is appropriated to the shagbark tree. Its 

 larvae frequently abound in the trunk, the solid wood of which is per- 



