HICKORY BARK BEETLES. 297 



It is probable that the young of this and other borers in the hickory 

 are devoured by two species of Cleridse bred by Dr. Le Conte, viz : 

 Chariessa pilota and Phyllobwnus dislocatus. The former has been ob- 

 served by Mr. Harrington in the act of devouring Agrilus egenus and 

 Mngdalis olyra. 



Several other species of Clerid beetles are said by Mr. Harrington to 

 commonly occur on the hickory and are beneficial to the tree. 



36. Xylehorus celsus Eichhoff. 

 Order Coleoptera; family Scoi.ytid^, 



This bark-borer has been bred by Dr. Le Conte from the twigs of the 

 hickory. 



37. Magdalia olyra (Herbst). 



Mr. F. 0. Bowditch, in the Quarterly Journal of the Boston Zoolog- 

 ical Society (1884), remarks that this weevil, which has heretofore only 

 been known to burrow in the red oak (see p. 80) has been found to infest 

 various species of hickory. The larvae " tunnel the bark in every direc- 

 tion, leaving only just enough tissue to prevent the bark warping away 

 from the tree." He adds : 



As far as my observations extend the species appears to prefer small trees, from 

 four to six inches in diameter. » * * jf h^q ^j.^^ jq gmall and very badly infested 

 it dies very quickly, and shortly after the beetles have escaped the bark is apt to 

 flake off or curl up in quite large pieces. 



38. Magdalis harhita Say. 



" The beetles," states Mr. Harrington, " are found during the sum- 

 mer months, puncturing the bark of dead and felled hickories, and the 

 larvae live in great numbers in the bark or between it and the wood. I 

 have found the beetles most abundant from the 15th to the 30th of 

 June." (Report, etc., 50.) 



The beetle. — Black ; prothorax closely punctured ; the rounded sides projecting in 

 front in a short acute tubercle. The head prolonged into a slightly curved beak, 

 not deflexed, and as long as the prothorax. The elytra have deep punctured striae, 

 and are as long as the head and prothorax together. Scutellum covered with white 

 hairs. Length, 6-7""". (Harrington.) 



39. Acoptus siduralis Le Conte. 



As this weevil is said by Mr. Harrington to bore abundantly in dead 

 hickories, in company with Magdalis olyra, it presumably infests living 

 trees. 



The beetle. — A small black weevil, densely clothed beneath and more sparsely above 

 with short yellowish hairs. The elytra are striated and in unrubbed specimens have 

 a wide band of yellowish pubescence across the base, and a narrow one near the tips, 

 which are black, as is also the space between the bands ; a white line along the 

 suture interrupts the basal band. (Harrington.) 



