182 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



HABITS OF SOME TACHINIDAE. 



BY R. C. SHANNON, Bureau of Entomology. 



It appears from recently collected Tachinids that nocturnal 

 habits may be more common in this family than we have sup- 

 ppsed. Mr. Walton has spoken at a previous meeting of the 

 society of Eutrixa exile Coq. as probably being nocturnal, he 

 having seen two specimens from Ithaca, N. Y., collected at light 

 and knowing that they are parasitic upon nocturnal beetles 

 (Lachnosterna) . Another specimen of this species was taken at 

 light at Plummer's Island, Maryland, in April, 1914. There 

 are three specimens in the National Collection which were bred 

 from adult Lachnosterna arcuata by Mr. Theodore Pergande in 

 March, 1895. Other nocturnal Tachinids have recently been 

 collected at light at Forest Glen, Maryland, by Mr. Otto Heide- 

 mann. One specimen is Cryptomeigenia theutis Walker, a well 

 known parasite of adult Lachnosterna, and four specimens are of 

 an apparently new species of Neophyto, which will be described 

 later by Mr. Walton. This latter species is probably parasitic 

 upon some nocturnal beetle, since its close relatives have such 

 habits. It may be that this species hides during the day, which 

 would perhaps account for it remaining unknown hitherto. The 

 nocturnal habit of these flies is clearly an adaptation to the noc- 

 turnal habit of their hosts. 



The genus Trichopoda has been known to be parasitic on 

 Hemiptera and recently has been bred on various occasions. Last 

 year several parasitized adults of the Coreid, Metapodius terminalis 

 were collected near Washington by Mr. Frederick Knab and 

 from one of these an adult Trichopoda was bred while another 

 on dissection disclosed a larva in the base of the abdomen. A 

 parasitized specimen of M. instabilis was found by the writer at 

 Dead Run, Fairfax County, Virginia, May 2, of this year and 

 from it a fine specimen of Trichopoda was bred. The larva left 

 its host and pupated on May 15, while the imago issued on the 

 29th. Parasitized specimens can be recognized at a glance since 

 the externally laid egg is white and is in strong contrast with the 

 body color of the host. Often more than one egg is laid upon a 

 single victim, Mr. Knab having in one case seen as many as five. 

 They are usually laid upon either the head or thorax, above or 

 below, but sometimes are even attached to the tegmina. 



Another genus of Tachinids has been bred from a different 

 genus of Hemiptera. A specimen of Reduviolus roseipennis 

 Reuter, in which the abdomen was swollen much beyond normal 

 size, was found on Plummer's Island, Maryland, May 10, 1914, 

 and was placed in an isolation vial, where, about a week later, 

 it was found dead with a dipterous puparium beside it. This 

 latter was placed in a suitable cell where the adult issued ten 

 days later. Mr. Walton determined it as Leucostoma atra Towns. 

 No host record of this Tachinid has hitherto been published. 



