May, '03] 



ENTOMOLOGICAL NEWS. 



147 



Notes on Some California Myrmecophiles* 



By Charles Thomas Brues. 

 There have recently come into my hands, through the kind- 

 ness of Dr. William M. Wheeler, some specimens of interesting 

 myrmecophiles collected and observed by Dr. Harold Heath in 

 California. One of them, a histerid beetle, belonging to the 

 genus HetcErius has been previously well known, but I am 

 enabled to record some additional facts concerning it ; another, 

 the larva of a syrphid fly is quite different from any of the 

 hitherto described forms of myrmecophilous Microdon larvae, 

 and seems worthy of extended description. 



COLEOPTERA. 



HISTERID^. 

 Hetaerius tristriatus Horn. (Fig. i.) 

 A male and female of this peculiar beetle were collected in 



a nest of Formica fusca L., 

 sub. sp. subpolita Mayr.,* at 

 Pacific Grove, Cal., during 

 the early partof April, which 

 is the only season of the year 

 when these insects are to be 

 found. Dr. Heath gives the 

 following short note concern- 

 ing their actions, ' ' when 

 first observed they were 

 about an inch below the sur- 

 face of the ground and were 

 being jostled about in the 

 excited mob of ants. To the 

 latter they gave little notice, 

 but rolled or tumbled over 

 each other; and finally when 

 quiet had been restored, remained motionless for ten or fifteen 



* Wasmann in his Kritisches Verzeichniss der Myrmekophilen und Ter- 

 mitophilen mentions H. tristriatus as occurring with Formica fusca, var. 

 subc^nescens Em , in Colorado and with F. obscuripes For., in Washing- 

 ton ; while Schwarz records it also as living in the nests of F. schau/tissi 

 at Helena, Montana. 



Fig. 



