54 SECOND REPORT OF THE STATE ENTOMOLOGIST. 



A locality near Lake Pleasant, Hamilton county, where the spruces- 

 were rapidly dying, was visited by him. As the result of a careful inves- 

 tigation made it was found that their death was owing to the countless 

 winding galleries made by one of the bark-mining beetles, Hylurgus 

 \^Dendroctonus\ riifipennis Kirby, between the bark and the wood. A 

 part of each was eaten by the insect, consisting of the newly-formed and 

 forming layers of wood and bark the most vital parts of the tree. Its 

 operations were therefore equivalent to a girdling of the tree. In one 

 instance, another of the bark-borers, of a much smaller size, Apate- 

 \_PoIygraphus\ rtifipetinis Kirby, was found associated with H. 7-ufipemiiSy 

 in its destructive operations. 



The report embraces an interesting discussion of the above attack, in 

 its character, localities of its occurrence, frequency with which the larger 

 trees show the attack, its cessation in some localities without apparent 

 cause, remedies for it, etc., for which the 28th Rcpt. of the N. Y. State 

 Museum of Natural History, 1879, pp. 32-38 may be consulted. 



In the 30th Report of the St. Museum of Natural History, 1878, pp. 

 23-25, Professor Peck has given additional observations on the spruce 

 attack by Hviurgus rufipciuiis and presented details of the o]jerations of 

 the beetle in the construction of its burrows. 



In his following Report, Prof. Peck describes an attack upon the 

 balsam fir, Abies balsamea, by another bark-boring beetle, observed by 

 him at Summit, Schoharie county, N. Y., through which a number of 

 trees had been killed and others were dying. The burrows were carried 

 underneath the bark in a horizontal direction, so that three or four oc- 

 curring at about the same height in the trunk would completely girdle 

 the tree and destroy its life. The beetle proved to be a Tomicus of 

 probably an undescribed species (31st Rept. of the N. Y. State Museum 

 of Natural History, 1879, pp 22, 23). 



The following determination, contained in a letter received by me 

 from Dr. LeConte, in December of 1877, is believed to refer to the 

 above insect: " Tomicus, related somewhat to the European species, 

 suturalis, curvidens and laricis — perhaps imported." Dr. LeConte de- 

 sired additional specimens " of the male with the hairy head " to be 

 sent to him, which probably for some reason, was not done. 



Dr. A. S. Packard, in his Insects Injurious to Forest and Shade Trees^ 

 1 88 1, pp. 219-227, has written of the destruction of spruces and firs in 

 Northern New England in 1 878-1881, and states, as the result of his 

 observations and of reports made to him, that the destruction of the 

 spruces was chiefly owing to three species of the cylindrical bark-boring 

 Scotytidw, viz., Pityophthorus puherulus, Xyloterus bivittatus, ^xwdi Xyleborus 

 ca^latus. ^\\t^t,d\dit^\)y Monohammus confusor,\vQXQ. also found to have 

 caused the death of large and healthy firs, a foot in diameter. 



