INSECTS AFFECTING PARK AND WOODLAND TREES 361 



with by the writer in balsam, spruce, hard and white pines, and in not a few 

 instances they were abundant enough to cause considerable injury and 

 materially reduce the*Tnarket value of the logs. This species, when numer- 

 ous, also appears able to exist in living trees. The writer found a number 

 of these grubs Oct. 16, 1901 at Bath-on-Hudson, working in living, appar- 

 ently healthy bark and with the point of injury indicated by wormlike 

 masses of pitch, showing conclusively that the grubs were operating in 

 living tissues. The tree under observation was apparently not infested by 

 any other insect and it appears probable that the beetles must have bred in 

 large numbers in nearby decaying, dead or dying trees and then, because of 

 the lack of more suitable conditions, attacked this living white pine. 

 Another case was observed during the same summer where the grubs of 

 this species were working in what appeared to be healthy pines and their 

 operations were to be observed here and there over a considerable propor- 

 tion of large trunks. It is remarkable how quickly this species infests a 

 dying tree, and in not a few other cases have we been led to question 

 whether the Monohammus larvae may not have followed the work of other 

 species very closely, even if its attack was not coincident with theirs. 



Early history. This species was noticed in some detail by Dr Fitch 

 under the name of M o n o h a m m u s notatus Drury. He characterizes 

 it, M. m arm o rat us Rand, and M. scut ell at us Say as the most 

 common and pernicious borers of pine timber in New York. He states 

 that felled pine timber allowed to remain in the forest through the summer 

 months is likely to surfer much injury from these borers, and adds that they 

 invariably make their exit from the wood on its upper side, and, as the holes 

 from which they issue admit water, the timber decays rapidly. 



This insect was noticed in 1877 by Rev. C. J. S. Bethune who states 

 that it is very generally destructive throughout Canada and the Northern 

 states, often being excessively abundant in pine regions. He cites Mr E. 

 Billings to the effect that he once saw a pine tree near Lake Clear, Renfrew 

 county, on which he calculated there were at least 300 individuals of this 

 species, while many others were flying about in all directions. Dr James 



