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killing young trees or seriously injuring older trees. From 18 to 26 

 eggs are deposited alternately along the main gallery. In 5 or 6 

 days these hatch and the larvae excavate rather long irregular mines, 

 pupating chiefly in the bark. This pest is not a very serious one, 

 and if the plantation is well cleared in the spring and dying and dead 

 trees biu-nt, there is little to fear from it. It occurs from British 

 Columbia to California. P. nebulosus, Lee, passes the winter as a 

 young adult and occasionally in the pupal stage. Emergence occurs 

 late in March or early in April, and recently felled or injured Douglas 

 fir is innnediately attacked. Saplings or limbs of large trees are 

 preferred, thick bark being avoided. The entrance gallery penetrates 

 the bark at a right angle and upon reaching the cambium the insects 

 start a gallery parallel to the grain of the wood, the female working 

 up the trunk and the male in the opposite direction. As the gallery 

 progresses the female makes small niches on each side in which she 

 deposits a single egg, closing up the niche with fine borings. From 

 15 to 30 eggs are deposited, which hatch in about 5 days, the larval 

 galleries recrossing each other many times. Beetles captured in the 

 wood had evidently passed the winter as young adults ; the first 

 eggs were laid in the cages in early April and the life-cycle of these 

 was completed by the end of May. A second generation occurs, the 

 adults of which remain within the bark until spring. The damage 

 done by this species would be very great but for the fact that it 

 prefers hosts that are already dying or injured. It attacks in 

 such numbers and the life-cycle is so short that control is difficult ; 

 the tree is in all probability past recovery before any outward signs 

 appear, except the fine dust-like borings that may easily be overlooked. 

 The use of trap trees should be a successful means of control. 



Pifyokteines (Dryocoetes) mi nidus, Swaine, is found in Douglas fir 

 from British Columbia to southern Oregon, in scattered localities. 

 The beetles were found to be mature and ready to leave the tree on 

 3rd June. They occurred in such vast numbers that in spite of their 

 small size the bark of the trees was honeycombed from top to bottom. 

 For this reason it is impossible to trace the pattern of any individual 

 gallery. This species is not widespread enough to be a serious pest ; 

 by felling and burning infested trees in the spring immense numbers 

 of the adults would be destroyed. Hylurgops rugipennis, Mann., has 

 been reported as attacking Pinus, Picea, Abies and Pseudotsuga, but 

 the author has never found it in Douglas fir, though abundant in 

 Pinus monticola and P. ponderosa, as well as a few individuals in Picea 

 engelmanni. In each case the insects had attacked trees that had 

 been down for years and were abundant in the decayed bark. In 

 the author's opinion it is a pest of secondary importance. Platypus 

 wilsoni, Sw^aine, has been recorded as attacking only sickly trees, 

 but the author has taken it from perfectly healthy examples of Abies 

 nobilis and Pseudotsuga taxifoUa in Oregon. All Pacific coast conifers 

 in a weakly condition are attacked, except the cedar group. The 

 mines extend directly through the bark into the wood. The female 

 deposits some hundred eggs loosely scattered about the gallery in 

 clusters of 10 or 12. The larvae require 5 or 6 weeks for development, 

 and feed on ambrosia fungus. The pupal cells are cut parallel with 

 the grain of the wood and generally occur in groups along the deeper 

 passages. This species is found in southern British Columbia, 



