STRIPED PINE-BORING BEETLE. 97 



it may be firstly in April, for breeding purposes. It is noted, however, 

 that it is in July at the latest that (in regular course) the first 

 generation will be found ready for flight, and then, and in August, 

 newly-laid eggs are again to be found in the brood galleries. The 

 beetles that thence originate from these eggs remain during winter in 

 the place of their birth, where Herr Eichhoff notes that he has seen 

 them often in imago state from November till March. 



Prevention and Eewedies. — Where the beetles of T. lineatum have 

 the option, they as a rule avoid " barked " * stems for egg-deposit, 

 especially when, at egg-laying time, the outer layer has become more 

 or less dry. But where this is still juicy, or damp from situation, or 

 other circumstances, then the stems which have been stripped of their 

 bark are liable to attack. Sickly coniferous trees are liable to attack, 

 and (with both species of beetle) broken wood and windfalls, or stumps, 

 are particularly liable to infestation. It is therefore advised that these 

 should be barked if their entire removal is not practicable. 



Much stress is laid on removal of the bark as a deterrent of attack, 

 but it should perhaps be noticed that in the case of this infestation 

 the removal of the bark is only a preventive measure, and not a remedy, 

 as it is in the case of our two great bark pests, the " Elm-bark Beetle " 

 [Scolyttis destructor) and the " Pine Beetle " [Hylurgus piniperda), in 

 which the beetles breed just within the bark, so that removal of the 

 nursery-ground gets rid at once of the nursery and its contents. With 

 the wood-boring Trypodendrons, the stripping of the bark only acts by 

 making the surface of the wood below it too dry to invite infestation. 



Where the beetles are very prevalent, trees from which the bark 

 has been taken may be attacked, and where this is to an extent that 

 makes preventive measures desirable, this wood should be removed 

 before March — that is, before the time of flight of the spring brood of 

 beetles. Felling in the growing season and immediate removal of the 

 bark is advised as a preventive. 



Traps may be arranged of wood felled for the purpose, or of waste 

 wood left about in July and August (the summer breeding-time) to 

 attract the beetles to lay their eggs instead of infesting valuable wood. 

 But these trees or branches should be kept under careful examination, 

 and when found to be attacked, should be stripped of their bark and 

 split up to destroy the larvae in the wood. 



The attacks are said to be worst where there are winter fellings, 

 presumably from the felled tree -trunks being in favourable condition 

 at return of spring for attack of the spring brood of beetles. 



* Perhaps for foreign readers who may favour me by looking over this paper, 

 it may be as well to mention that a " barked " stem is not one with bark on it, but 

 one from which the bark has been taken. 



H 



