630 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 57. 



During the first part the prothorax of the Clerid rested on the lower side of 

 the bottle, body of the Clerid upside down. Later the front of the body was 

 lifted clear of the floor and the meal was finished in midair. 



The two front pairs of legs were used to grasp and turn the victim, much as 

 a squirrel holds a nut while eating it. The Clerid ate ravenously of the interior 

 of the prothorax, inserting the jaws between the head and thorax. Finally, the 

 head and thorax being severed from the abdomen, the Clerid finished up on this. 



They mate and oviposit at this time. The eggs are deposited in 

 the entrance galleries of host. The larvae upon hatching crav^l 

 through the galleries and mines, feeding upon the barkbeetle broods. 



According to W. S. Fiske (in notes) the pupal cells are made in the 

 bark of the tree. Adults ready to emerge observed Apr. 23. 



Distribution: Western and Middle Western United States; also 

 recorded from Michigan and Wisconsin. 



Observations by Hopkins, Webb, Fiske, Edmonston, Burke, Cham- 

 plain. 



Genus PLACOPTERUS Wolcott. 



PLACOPTERUS THORACICUS Olivier. 



Is a predator on the smaller barkbeetles and borers in twigs and 

 limbs of deciduous trees. W. F. Fiske states in his notes : " This 

 species vras very common in the jarring for Curculio in Georgia in 

 1901. And "without question is an enemy of Scolytus rugulosus.^^ 



The adults may be taken during the summer months upon the 

 foliage of trees and sometimes on flowers. 



Early larval stage not noted. At Lyme, Connecticut, it over- 

 winters in the abandoned pupal cells of Magdalis olyra in hickory 

 and probablj' prey upon the Magdalis broods. Also found over- 

 wintering in the galleries of Oncideres in hickory twigs, infested 

 with Ghramesus iconae, and in butternut twigs infested with small 

 Cerambycid larvae. 



The larvae were all prepupal in their cocoon-like cells, lined with 

 the frothy exudation and attached to the wood. 



Observations by Hopkins, Fiske, Champlain. Pennsylvania, Kirk, 

 Knull. 



Genus ENOCLERUS Gahan. 



Some of the species of this genus are the most important predators 

 on barkbettles and might be utilized to considerable advantage in 

 control measures. 



The general habits of the different species vary considerably. 

 One species is active at night, others in daylight. Some are to be 

 found on flowefs, where they feed to some extent on pollen; others 

 are never found on flowers. 



All of the species studied line their pupal cells heavily with an 

 exudation that is foam-like in substance, of a silvery luster, mak- 

 ing a smooth interior, attaching exterior to the bark or if cells are in 



