TOMICUS LINEATUS. 255 



winding and sparsely distributed; both kinds of galleries may 

 be clearly seen on the sapwood, though those made by the 

 larvae are more marked in the bast. 



This beetle readily attacks woods which have suffered 

 from fire. Trees which have been severely attacked may be 

 recognised by the yellowish colour of their crowns. 



d. Protective Rules. 



As for T. laricis, L. ; but trap-trees are useless. Instead 

 of these, branches may be used as traps, which should be 

 burned as soon as they are stocked with larvae, and replaced 

 by fresh ones every 4 to 5 weeks until the autumn. Poles 

 seen to be attacked by larvae should be immediately felled and 

 barked, and the bark burned. 



7. Tomicus acuminatus, Gyll. 



Beetle 3 to 4 mm. long ; brown, with yellow-grey pubescence. 

 Elytra regularly punctate-striate, the excavation circular, 

 acuminate at the apex of the suture, its elevated margin with 

 3 teeth on either side, the first a small tubercle, the last the 

 largest, and situate about the middle of the margin. 



Life-history, etc. 



This species chiefly infests the crown of full-grown or old 

 Scots pines. The mother-galleries consist of 3 to 5 branches, 

 radiating from a spacious pairing-chamber and grooving the 

 sapwood rather deeply when excavated in thin bark. The 

 larval galleries are twisted, frequently coming into contact or 

 even crossing, but as a rule scarcely marking the sapwood. 



The species, though not very common in Europe, is not 

 rare in Scotland and the north of England, and must be con- 

 sidered as one of our injurious species. Its attacks must be 

 treated on the same lines as those of other species of Tomicus. 



8. Tomicus lineatus, Oliv. 



a. Description. 



Beetle 3 to 4 mm. long, short and cylindrical, black, the 

 hinder part of the thorax and the elytra yellowish brown. 



