212 



PROCEEDINGS ENTOMOLOGICAL SOCIETY 



A CURIOUS HABIT OF ONE OF OUR PHORID FLIES. 

 BY NATHAN BANKS. 



One day last summer, while walking in the woods near my 

 home, I saw a myriopod (Party id us sp. ) wriggling and twist- 

 ing on the dead leaves in a most excited and erratic fashion. 

 Bending down, I saw that a number of tiny flies were darting 

 at the myriopod, which was trying to keep them off and to 

 hide in the leaves. I swept with my midget net and caught 

 one of the flies, the others and the myriopod disappearing 

 among the dead leaves. In a moment they reappeared, the 

 myriopod as excited as ever, and endeavoring to escape his 

 tormentors. I swept again and secured a second fly, but this 

 frightened the others away, and I did not see them again. 



On examination the flies were found to belong to the 

 phorid genus Aphiochceta, near to A. nigriceps, or A. picta, 

 but distinct from both. 



The habits of Aphi- 

 ochceta are various. 

 Several have been 

 bred from fungi, oth- 

 ers from dead or de- 

 caying insects, but 

 there is no record of 

 this or any other phor- 

 id attacking a myrio- 

 pod. It, however, is 

 not certain that the 

 fly breeds in the my- 

 riopod, either dead or 

 alive; it may be that 

 it is attracted by the 

 exudation of these 

 myriopods, which 

 they secrete when dis- 

 turbed. 



After this I learned that Mr. Barber and Dr. A. K. Fisher 

 had this year also observed the same habit in the same species 

 of fly; Dr. Fisher with the same myriopod; Mr. Barber with 

 a species of Spirobolus. 



I describe the phorid as follows: 



Aphiochseta xantippe, new species. 



Female. Yellowish; head and thoracic notum yellowish brown, ab- 

 domen dark brown above, except the tips of segments pale, last two 



Fre. l.Apliiofliirfa .r<mtij>j>e Banks, and bristles 

 on the front of head. 



