INSECTS AFFECTING PARK AND WOODLAiND TREES 295 



Minute oak bark beetle 



Pifypplitlioriix minutissiunts Zimni. 



A niiiuite slender, dark Ijrown beetle, ahoul '„ „, inch long, sometimes riddles the dead 

 inner Ijr.rk of red oaks. 



This species was found by llu- writer in great numbers at Manor, Oct. 

 3, 1900, minino- the bark of piled red oak cord wooil which was j)rol)al)ly 

 cut the preceding- winter. Dr A. D. Hopkins has recorded this species as 

 infesting black oak, wliite oak, jack oak, chestnut oak and dogwood, and he 

 has observed a chalcid tly attack the a(hilts. This species has also been 

 recorded b\- Dr Riley as mining the dry oak bark. 



Description. The adult is a small, rather slender dark brown beetle, 

 about ' |i,.inch long. The head is ornamented with two bunches of yellow- 

 ish, curved hairs. The prothoraN is rather coarsely tuberculate and the 

 wing covers or eh'tra are very finely striated. Certain structual details of 

 this beetle are shown on plate 67, figure i i, and its method of work on 

 plate 39, figure i. 



The beetle runs its galleries transversely to the bark fibers, depositing 

 eggs on either side, the young hatching therc^from work at nearly right 

 angles to the parental grooves and therefore' nearly parallel to the grain of 

 the wood. This insect, when present in nimibers, soon riddles the bark and 

 as the nunu:rous cNit holes allow ready access to moisture, decay soon fol- 

 lows. This can hardly be considc-red a species of much importance, except 

 as it aids in hastening the decay of the wood, sinct- it apparently confmes 

 its operations to dead bark. 



A small beetle, S i 1 v a n u s s u r i n a m e n s i s Linn., was r(iart'd from 

 a piece of infested bark, and it was evidently living on either decaying 

 vegetable or animal matter, rather than pre\ing on this bark borer. 



Bibliography 

 1893 Hopkins, A. D. W. Va. Agric I'.xp. Sta. liul. 32, p. 20<S, 228 



