736 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 



chrysalis state, it either transforms within a small branch in the pith or 

 under the bark. In the latter case it sinks an oval cylindrical hole in 

 the pith wood, and builds up over it, in the space between the loosened 

 bark and the wood itself a white covering, composed of the long chips 

 or fibers of the pith wood, the little fibers being closely interwoven and 

 matted together, so as to form a cocoon of a tolerably firm consistence, 

 which contrasts in its white color with the under side of the bark. The 

 cocoon thus made is not usually, if ever, lined with silk. The length of 

 the entire cell is 12™""; its breadth is 5°i™. Hylurgus terebrans con- 

 structs similar cells, but they are much smaller. Most of the bark- 

 borers, however, do not transform in such cells, but in their tunnels. 



While the insect is especially abundant in Maine, I have also found 

 it .in abundance in September on the ornamental white pine bushes on 

 the grounds of the State Agricultural College, at Amherst, Mass. When 

 the white pine is set out on plantations it has thus far been tolerably 

 free from the attacks of this pest. On the extensive plantation of Henry 

 G. Eussell, esq., at Greenwich, R. I., who has planted trees on a larger 

 scale than any one else in New England, only scattered trees have been 

 affected. Fig. 2, Plate xxvii, has been drawn from a terminal twig on 

 one of these trees. Part of the twig was mined under the bark, the 

 tunnels ran close together, there being seven or eight on one side of a 

 twig about a third of an inch in diameter. They run up and down 

 the twig, more or less parallel, beginning small, when the larvte hatched 

 and becoming slightly larger as the grub grew, until at the end of 4 

 or 5 inches they sink into the cell, the grub having become full-fed 

 and making its cell designed for its final transformation. 



When the pith is mined, the cells form enlargements of the tunnel, 

 and- in the case before us the cells are so thick as to touch each other, 

 there being six cells in a length of not over two inches. When the cells 

 are made exteriorly, but under the bark, they are usually about an 

 inch apart, and as we have said, at once by their light color and convex 

 surface, attract attention when the bark is torn off. 



While this weevil does much injury to the young white pine trees, it 

 is by no means restricted to such growths, but lays its eggs in the bark 

 and mines the sap-wood of large pines and other coniferous trees. 



Thus I have found the beetles more commonly, and in different stages 

 of growth, in the white pine April 24; at this date the beetles begin 

 to appear; and the beetles do not all make their exit from under 

 the bark and fly about by the end of spring, but I have found the beetles 

 under the bark May 30, and even as late as the 11th of August, when 

 a pupa and beetle occurred, the latter somewhat pale and immature. 



This weevil is of common occurrence in the bark of spruce trees 6 to 

 10 inches in diameter, where I have found them during the middle of 

 August at Brunswick, Me. The grub and pupa occurred near the Glen 

 House, White Mountain, New Hampshire, at the end of July in the fir ; 

 on the 30th of July I took five mature beetles from under the bark of 

 a hemlock tree. I have never noticed, however, spruce, fir or hemlock 



