632 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 57. 



ENOCLERUS SPINOLAE LeConte. 



Clerid common, larvae in pupae cases in outer bark of Yucca. Hes- 

 peria, California, May 12. Observations by Dr. A. D. Hopkins. 



ENOCLERUS MOESTUS Klug. 



Adults active during daytime, July, August. Observed on various 

 coni'fers (in Colorado) and is probably a predator on barkbeetles and 

 other borers. Especially common on small pinon pine infested with 

 barkbeetles and small Cerambycid larvae. Seems to range slightly 

 higher in altitude than does E. sphegeus in Colorado. 



Collected on tanglefoot screen. August. Altitude 7,500 feet. Ob- 

 servations by Edmonston, Hofer, Champlain. 



ENOCLERUS SPHEGEUS Fabricias. 



Is an important predator on Deridroctonus and other barkbeetles 

 in the Western States. My studies were made in Colorado, where 

 it is predaceous on barkbeetles in various conifers at elevations rang- 

 ing from 6,000 to 8,000 feet. 



It is an important enemy of Dendroctonus ponderosae Hopkins 

 and its history in comiection with this species is as follows: 



Adults. — The adults appear in June and are at once attracted to 

 infested trees. These trees would contain overwintered broods in 

 the case of D. ponderosae.- On sunny days the adults may be ob- 

 served running about mating or feeding. They may remain motion- 

 less for a considerable time while waiting for their prey, but drop 

 or fly when disturbed. Their food consists of any small insects 

 that are attracted to the infested trees, principally barkbeetles. 

 They are able to handle objects three times their own size, but pre- 

 fer smaller objects. The adults continue to live during the warm 

 summer months, sometim.es four or five months. 



Eggs. — The eggs are deposited soon after the adult emerge, lat- 

 ter part of May or June. The eggs are placed in trees that con- 

 tain Dendroctonus {D. ponderosae) broods and must hatch soon after 

 being laid, as the larvae must feed and make their growth before 

 the Dendroctonus beetles emerge. 



Larvae. — The larvae, being voracious feeders, grow rapidly, and 

 during this time they consume many Dendroctonus larvae and pupae. 



About the 1st of August the Dendroctonus broods consist mostly 

 of adults ready to emerge. Now we find the almost full-grown 

 Clerus larvae wandering about among the galleries and beneath the 

 bark. 



Upon the emergence of the Dendroctonus broods, the Clerid 

 larvae being full grown, go into the ground at the base of the same 

 tree for hibernation. This migration occurs at night. They enter 

 the ground and burrow for several inches in depth close to the 



