13 



little time for actual work in the field. Realizing that this would be 

 the case, I devoted my attention to the investigation of a few leading 

 features which promised to yield the best results. 



INFORMATION ON THE HABITS OF SCOLYTIDS MADE THE PRIME OBJECT. 



Previous to this trip little had been published regarding the host 

 plants and habits of the Scolytidse of the Northwest, and scarcely any 

 observations had been made on the relation of this destructive class of 

 insects to the unhealthy conditions of the timber. I felt, therefore, 

 that with my previous experience in the study of these insects in the 

 forests of West Virginia, it was my first duty to obtain as much infor- 

 mation as possible regarding the habits of those found in the localities 

 visited, and I spared no pains or labor to accomplish this end. As a 

 result of this effort specimens of some sixty species of Scolytids, 1 rep- 

 resenting some twenty genera, were secured. This includes nearly all 

 of the species heretofore known from northern California, Oregon, 

 Washington, and Idaho. It also includes a large number heretofore 

 unknown from this region, with representatives of two or three new 

 genera. The host plants and some features of the habits and life his- 

 tory of every species were determined. A large series of biological 

 material of both the undescribed and described species was also col- 

 lected. 



PRINCIPAL SCOLYTID ENEMIES OF THE FORESTS OF THE NORTHWEST. 



The genus Dendroctonus. — This genus, which has been found to con- 

 tain some of the most destructive enemies of the conifers of the East, 

 was found to be represented in the Northwest by three described and 

 two or three undescribed species. They were found here, as in the 

 East, to be the principal enemies of pine, spruce, and larch; and from 

 what was observed of their habits it is plain that under favorable con- 

 ditions most, if not all, of them are capable of attacking and killing 

 healthy timber. 



One species which I have provisionally identified as Dend/roctonus 

 hrevicomis Lee. 8 was found to be a most destructive enemy of the 



x This is the number of the species determined by Mr. Schwarz and myself in a 

 preliminary study of the entomological material. Subsequent identification of the 

 mounted specimens may show that there are a few more or a few less species and 

 genera. 



2 Heretofore this species had not been recognized since if was first described by 

 LeConte. Dr. Dietz, in his notes on species of Dendroctonus of boreal America, states 

 that he does not recognize any difference in typical specimens of D. frontalis Zimm. " 

 and D. hrevicomis, Lee, and consequently concludes that they are identical. The 

 examples I found are undoubtedly distinct from D. frontalis, although very closely 

 allied to this species in specific characters and habits. It agrees so closely with 

 Le Conte's description of D. hrevicomis, however, that I think it must be recognized 

 as such until a comparison With the type proves the contrary. 



