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are probably predaceous on it. Both adults and larvae of the 

 Clerid beetle Clems sphegeus, F., feed upon all stages and are important 

 enemies. Cicindela longilabris, Say (tiger beetle), an Asilid, Dasyllis 

 posticata, Say, and an unidentified species doubtfully referred to the 

 same genus, are all predatory on this beetle. 



To7nicus (Hylastes) nigrinus, Mann, (red fir root borer) in the larval 

 stage excavates long winding tunnels in the bark of the roots of Douglas 

 fir. This species occurs from Alaska to California, but is not numerous 

 or economically important. Hylastes ruber, Swaine, attacks dying or 

 weakened Douglas fir. Scolytus unispinosus, Lee, attacks Pseudofsuga 

 taxifolia, P. mucronata, Larix occidentalis and Picea engelmanni. 

 The species from the two last-named trees may be a closely 

 related beetle and not the true S. unispinosus. The latter which 

 occurs in the Pacific coast and Rocky Moimtain States and in 

 south-western Canada, excavates two short straight longitudinal 

 galleries from an entrance burrow in living bark of injured, dying or 

 recently felled Douglas fir and western larch. From 40 to 100 eggs 

 are deposited in crevices in the sides of the main gallery, and these 

 hatch in 4 or 5 days. Eggs and young larvae are commonly 

 found in March and adults of this generation appear in late April 

 and May. Eggs and larvae have also been found in late August at 

 4,000 feet, indicating at least two generations. The winter stage has 

 not been observed. Although this species does kill some small living 

 trees, it is not regarded as a serious pest. An undetermined Hymenop- 

 terous parasite has been bred in numbers from its galleries and a 

 Chalcid, Denotus scolyti, Ashm., has also been recorded as a parasite 

 of this species. E. tsugae, Swaine, attacking Tsnga mertensiana and 

 Pseudotsuga mucronata, and E. monticolae, Swaine, attacking Pitms 

 monticola and Pseudotsuga mucronata, are both found in British 

 Columbia. 



Pseudohylesinus grandis, Swaine, occurring from British Columbia to 

 California and eastward to Idaho and Colorado, apparently attacks only 

 Douglas fir in any stage of growth, being especially bad in saplings 

 and limbs of old trees. Adults appear early in April and construct 

 the primary gallery, in which about 25 eggs are deposited by each 

 female. These hatch in 10 to 15 days ; the larval galleries are begun 

 at right angles to the main galleries, but finally turn parallel to it. 

 These pierce both bark and wood, the pupal cell invariably being in 

 the bark. About 6 weeks is required for the life-cycle. In some 

 localities only one generation a year is recorded, but in the Willamette 

 Valley adults emerging in June re-attack the same tree or move to 

 a new host and rear a second generation, which is mature by the 

 middle of September. The adults of this second generation hibernate 

 in the mines. This species principally confines itself to the limbs of large 

 trees in a weakened or dying condition. Large numbers of unidentified 

 parasitic Hymenoptera have been bred from the galleries. Many 

 dead larvae were found infested by bacteria. Experiments will be 

 made to determine whether this disease was the cause of death and 

 whether it is fatal to other members of this family, especially to the 

 genus Dendroctonus. Pseudohylesinus granulatus, Lee, attacks Abies 

 grandis in eastern Oregon and sometimes Douglas fir. The adults 

 excavate short transverse galleries in the cambium of the main trunk 

 or the large limbs of healthy, weakened or recently felled trees, often 



