THE PINE INVESTIGATION. 311 



Just as we were leaving the forest, and too late to look for 

 Clerids, a small spruce tree was observed that was evidently dy- 

 ing from the attack of the bark beetle, Pityogenes curvidens. 

 A hurried examination revealed a number of examples of this 

 species. 



We returned to Aberschwiller at 5 p. m., wet and tired from 

 our day's tramping through the forest in the rain. It had not 

 only rained hard all day, but had turned quite cold which con- 

 tributed all the more to our discomfort. 



RETURN TO HAGENAU. 



The next morning we returned to Hagenau where we arrived 

 at 9 a. m., and after luncheon we proceeded to the forest where 

 in four hours 1 collected 225 examples of the Clerid. Mr. Bal- 

 douf, (the Landforestmister), my 

 guide, and the driver together 

 secured 175, making 400 living 

 specimens collected in that bhort 

 time, which is sufficient evidence of 

 the abundance of this insect where 

 the conditions are favorable for it. 

 A large number, possibly 250 or 

 more, were either killed or injured 

 in cutting them out of the bark. 

 Since these were of no value to us 

 they were not taken or even count- 

 ed. The Clerid was exceedingly 

 common in the bark of some of the 

 injured trees, and was frequent in 

 all that were infested by the bark 

 beetles. 



OBSERVATIONS ON THE HABITS OF Flg . xxXIX.-Adult of European 



bark beetle destroyer, dorsal view. 



CLERUS FORM1CARIUS. Small fl 8 ur e on the right natural 



size. 



From what I observed of the relation of the Clerid to the pine 

 bark beetles, M. pinipeda and M. minor, which are among the 

 principal enemies of the European pine forests, it was evident 



