INSECT ENEMIES OF THE REDWOOD. 33 



larvfe begin to form their cocoons in December and January, being an evidence that 

 the insect is double brooded. The larvre when fully grown line the channel in the 

 resinous nodules with silk, forming a sort of cocoon, in which they transform to 

 pupae. 



This insect was observed b}^ the writer in September. 11M)2. in the 

 vicinit}^ of Del Monte. Cal., where it occurred in the matured larval 

 stage in large masses of pitch on the trunks of living Monterey Pine. 

 According to information from Mr. Lee, the gardener in charge of 

 the Del Monte grounds, it does considerable damage to the tree. 



The work of probably the same insect was also observed in the same 

 grounds on Lawson's Cypress, causing deformities on the main trunk 

 and branches. 



REMEDY. 



In comparativeh^ small areas it would not be difficult to dig the 

 worms out of the pitch with a knife during the fall and winter months. 

 This would serve to greatly reduce their numbers and to prevent seri- 

 ous depredations in future. In the case of larger areas of forest trees 

 there is. so far as known, no practical remedy. 



CEDAR BARK-BEETLES. 



There is a certain class or genus of bark-boring beetles which, so 

 far as has been determined in different countries, inhabits only the 

 cedar and cedar-like trees. Owing to this habit they may properly be 

 termed cedar bark beetles. The}^ belong to the order Coleoptera, 

 family Scolytidai, and genus Phlceosinus. Two species of this genus 

 were found by the writer in living and partly living bark of recently 

 felled Redwoods near Guerneville, Cal., in April. 1899. 



The Redwood Bark-Beetle. 



{Phloeosimis sequoix Hopk. MSS. ) 



This is a common species, which heretofore has been confused with 

 a much less common one described b}^ Dr. Le Conte under the name 

 cristatus. It is a medium-sized, stout, black beetle (tig. 1), the male 

 and female of which bore through the outer bark and excavate long, 

 nearh" straight burrows or galleries through the inner living or dying 

 bark and surface of the wood, as shown in the illustration, Plate 

 XII. The eggs are closely placed along each side of the gallery in 

 little notches excavated for the purpose. These soon hatch into minute 

 white grubs, which immediately commence to feed upon the inner 

 layers of bark and outer layers of wood. They continue to feed thus, 

 extending meanwhile their food burrows, and increase in size until 

 the}^ attain their full growth as grubs (larvae). Then they enter the 

 wood for a short distance and excavate a cavity or kind of cell, in 

 which they change to the inactive or pupal stage. Here they remain 

 12478— No. 38—03 3 



