Ftirniture Beetles. 23 



when the time for pupation is near,' and leave only a small thick- 

 ness for the beetle to bore through in order to get outside. But 

 in the case of the common furniture beetle and of the death-watch 

 beetle, larvae of a later generation and in an earlier stage of 

 development may at the same time be in the deeper parts of the 

 wood. 



If liquids be applied at the time of pupation or just before, the 

 larvae near the surface of the wood may be reached and killed, 

 while those in the deeper parts would probably be untouched ; but 

 twelve months later these larvae, in their turn, would come near 

 the surface to pupate, and then another application of the liquid 

 should be made. The eggs are more resistant than the larvae or 

 beetles to the action of a liquid or a gas, and the pupae probably 

 are so, too ; and treatment with a liquid or gas is best, perhaps, 

 applied either before pupation takes place or after the young larvae 

 have hatched out — that is, in the case of the common furniture 

 beetle, about the middle of May and the end of July or beginning 

 of August. With the other species, earlier. It would be better 

 still to give a treatment at both periods — one, say, in May, to be 

 followed by another in July or August. Heat, if sufficient to raise 

 the temperature in the interior of the wood to 130° F., will kill all 

 the insect life inside, and may be appUed at any time, although 

 heat also would have a better chance of reaching the larvae if 

 applied at the time when they are nearest the surface. 



Whatever method be adopted, there is always the possibility 

 that some of the eggs or larvae may for the time being escape, 

 but if the treatment be repeated and given at the best period 

 each year for a few years in succession, any one of the methods 

 mentioned should in the end prove successful in completely 

 eradicating the worm. 



