THE LEAD-CABLE BOEER IN CALIFORNIA. 



13 



The histerid. larvae appear to be more common in the mines of the 

 Lyctus. The predator Trogosita virescens Fab. was reared from in- 

 fested wood. No Hymenoptera or Diptera were observed in any of 

 the rearings that could be determined as actual parasites of or 

 predators on Scobicia. 



LIFE CYCLE. 



According to the observations made at the Los Gatos laboratory, 

 the life cycle of the cable beetle is as follows: The mother beetle 

 excavates an ^gg gallery or burrow in the solid wood and lays her 

 eggs in the pores of the wood from this. (Figs. 10, 14.) The eggs 

 hatch in about 21 days. The larvse mine in the wood (PI. Ill, Figs. 



Fig. 9. — Diagram illustrating seasonal history of the California lead-cable borer. 



4 and 5 ) for about nine months, molting about six times. They then 

 become quiet and remain as prepupse for about six days, whereupon 

 they pupate. The pupa stage lasts for about 14 days and then the 

 transformation to the young beetles occurs. The beetles remain in 

 the wood about 30 days, hardening and maturing. (PI. Ill, Fig. 2.) 

 They then eat their way through the outer wood and bark, emerge, 

 and, if females, start new galleries in the same or another section 

 of wood. (PL III, Fig. 1.) About the time the galleries are started. 



