5CX> NEW YORK STATE MUSEUM 



Xylonomus albopictus Cress. 

 Specimens of this parasite were cut from hickory infested by D i c e r c a 

 obscura van 1 u r i d a Fabr., on which it was probably parasitic. It has 

 been recorded by Dr Hopkins as a parasite of buprestid larvae. 



Foenus tarsatorius Say 

 This insect was observed oviposting on butternut. It is undoubtedly a 

 parasite of some wood borers infesting this tree. 



American bark beetle destroyer 



Thanasivius diibius Fabr. 

 This is one of the commoner, larger clerids. It measures nearly^ inch 



in length, and may be recogni'^ed by the head, thorax and basal portions of 

 the wing covers being a dull red. The remainder of the wing 

 covers is jet-black, except for the irregular transverse, silvery 

 markings. This predaceous bark beetle was observed in 1901 

 in small numbers on white pine which had been nearly killed 

 by bark borers at Bath-on-Hudson, and several beetles and 

 a number of larvae were seen, though only one adult was 



Fig. 12, T h a n a s i - capturcd. 



mus dubius, en- _ _ 



larged (original) Thls specles has been met with repeatedly by Dr Hopkins 



in his investigations of insects affecting forest trees in West Virginia, and 

 he states that this form is the one most closely related to the European 

 species,. C 1 e r u s formicarius Linn., which was introduced by him in 

 1892, in the hope that it would prove a very efficient agent in preventing 

 serious outbreaks of bark borers. 



The American bark beetle destroyer passes the winter in all stages 

 from larva to adult, as stated by Dr Hopkins, in the bark under which it 

 breeds and sometimes in the loose bark and moss at the base of the tree. 

 The beetles appear in the spring, and soon after bark beetles begin to 

 emerge from their winter quarters, fly to infested trees, logs or tops, where 

 they station themselves beneath loose flakes of bark, awaiting an opportu- 

 nity to pounce on their prey. They also move rapidly over the bark in 



