Vol. XI] 



COLE AND LOVETT—L1ST OF OREGON DIPT ERA 



209 



50. Trichocera trichoptera O. S. 

 Forest Grove in Dec, Jan. and Feb. (Cole). C. P. A. 



det. 



Family DIXID^ 

 Small slender flies, all belonging to the genus Dixa. There 

 are eight species listed from North America. The adults 

 resemble mosquitoes but are not pilose and do not bite; they 

 are found in moist localities where there is abundant vegeta- 

 tion. The larvae are aquatic and resemble mosquito larvae. 



51. Dixa centralis Loew 

 Hood River, X-l (Cole). 



Family PSYCHODID^ 



Fig. 3. Psychoda cinerea Banks. 



The moth-flies are attracted to lights in great numbers. 

 Some are found on tree trunks and many in damp, shady 

 places, often on the undersides of leaves or on the surface 

 of some stagnant pond. They are also found on windows 

 and in outhouses in the winter and spring. 



Many of the species have aquatic larvae, Maurina (Peri- 

 coma) preferring swift streams and being provided with 

 ventral suckers on the abdomen. Some larvae occur in cow- 

 dung and in decaying vegetable matter. The larvae have 

 spiracles and tracheal gills. 



