15 



the unhealthy condition of this pine in its native home (Monterey 

 County, Cal.) was probably due to the attack of this or of a closely 

 allied bark beetle. The fact that it was not found in spruce, fir, or 

 larch indicates that in the Northwest, as in the East, this large repre- 

 sentative of the genus almost exclusively infests the pine. Its habit of 

 attacking trees at the base is the same as in the East, as are also the 

 social habits of the larvae. 



The information I was able to gather of the habits and different 

 stages of the Western representatives of D. terebrans, of which nothing- 

 had been recorded, will aid greatly in arriving at definite conclusions 

 regarding the identity of numerous doubtful forms collected on this 

 trip, and those among the large series of material in the national col- 

 lection. 



Another Dendroctonus, referred to in my notes as " Dendroctonus sp., 

 near ruTfpennis" proved upon comparison with identified specimens in 

 my collection to be the same as examples labeled D. similis. 1 It appears 

 that nothing has heretofore been recorded regarding the host trees or 

 habits of this insect, yet I found it to be one of the commonest bark 

 beetles of the region traversed, and a special enemy of the red fir 

 (Pseudotsuga taxifolia). It was especially abundant wherever this 

 tree was being cut for fuel or lumber. Partially developed broods 

 were in the bark of trees felled the previous j^ear, and some had emerged 

 and were entering the bark of logs and stumps of recently felled ones, 

 in the living bark of which they were excavating galleries and depos- 

 iting eggs. On a small military reservation at Port Williams, Wash., 

 I found it associated with the death of large numbers of red fir, 

 and in eastern Washington and northern Idaho it was found to be quite 

 as common an enemy of the Western larch (Zarix occidentalis) as of 

 the red fir. The fact that it was found so common in these two kinds 

 of trees, and not in Picea or Abies, suggests that there is possibly a 

 closer affinity between Pseudotsuga and Larix than has heretofore 

 been recognized by botanists. 



An undescribed Dendroctonus, near D. rujipermis, was found m the 

 bark of Tideland spruce near Newport, Oreg. This beetle is repre- 

 sented in the national collection by a few large, black examples from 

 Queen Charlotte Island, and in my collection by a large series recently 

 sent to me for identification from the same island by the Reverend 

 Keen. This is very likely a special enemy of the Tideland spruce, 

 and, judging from the habits of other species of the genus, will doubt- 

 less prove at times quite injurious or destructive. 



The genits Scolytus. — This genus, which is represented in the East by 

 three common species which depredate on deciduous trees (viz, Scolytus 

 'rugulosus on fruit trees, S. qiiacfaispinosus on hickory, and S. muticus 



1 This may, after all, prove to be D. obesus Mann., which LeConte believed to be 

 synonymous with D. rufipennis, (Rhyiichophora of North America, 1876, p. 385.) 



