PINE BARK-BEETLES. 709 



under the breast. By transverse impressed lines it is divided into 

 thirteen segments, the head being counted as one. Its head is polished 

 and white, at least during the first periods of its life, with its mandibles 

 chestnut brown, and no indications of eyes, and no feet, but with their 

 places supplied by two small round retractile teat-like protuberances on 

 the under side of each of the three segments next to the head. Having 

 completed their growth, they sink themselves into the wood to repose 

 during their pupa state. The small round hole which they perforate 

 in the wood for this purpose is seen at or near the outer end of each 

 barrow in which the worm has lived to reach maturity. 



The pupa resembles the perfect insect in its size and shape, with the 

 rudimentary legs and wings inclosed in sheaths and appressed to the 

 outer surface of its body in front. After taking on its perfect form it 

 jierforates a small round hole through the bark and comes out from the 

 tree." (Fitch.) 



Bark-borers of this genus are said by Le Oonte to have the body stout, 

 cylindrical, with the slope of the elytra oblique, scarcely flattened ; the 

 funicle of the antennae with four distinct joints, and the sensitive sur- 

 face of the antennae concentrically anuulated. In the present species 

 along the slope of the elytra are two prominent tubercles and some 

 smaller marginal ones, the elytra are strongly punctured in rows, the 

 interspaces with rows of distant punctures, while the tibiae are strongly 

 serrate. 



From eight hundred to a thousand specimens of this bark-borer, with 

 hundreds of larvae and many pupae, were found in July and August at 

 Brunswick, Me., under the bark of a white pine stump about 22 inches 

 in diameter, the tree having been cut down the preceding November. 

 The bark was honey-combed with its holes, the pupae resting in cells in 

 the bark. The mines usually run obliquely through the thick bark, not 

 sinking into the sap-wood, so that no regular mine was formed, and it is 

 difficult to give a good description of it. The diameter of the track and 

 of the hole for the exit of the beetle is slightly larger than that of Xylo- 

 terus Mvittatus. It is often two-striped, but this is due to the fact that 

 it begins to turn dark in the middle of the elytra after transforming. 

 It also occurred in abundance under the bark of the spruce, in the 

 same place, associated with X bivittatus. 



Two Scolytid or bark-boring beetles were observed in abundance. 

 May 30, 1882, near Providence, under the bark of white pines {Pinus 

 strobus), engaged in reproduction and egg-laying. The larger of these 

 was Hylurgops pinifex Fitch, the smaller Xyleborus cwlatus Eich. 

 Bringing specimens to my house, the next day I was able to observe 

 their habits more closely. The following notes refer entirely to X. 

 ccelatus. The female was in her hole, the end of her abdomen extend- 

 ing straight up out of the perpendicular hole or " mine;" a male ap- 

 proached her and rubbed the end of her body with his fore pair of feet, 



