FUNGUS GNATS OF NORTH AMERICA. II5 



This genus also would be placed with the Mycetophilinae in 

 the classification of Enderlein. 



Pnyxia scabiei Hopkins. 



Proc. Ent. Soc. Wash. Ill, 152. 1895 (Epidapus). 



Male. Length i to 1.5 mm. Antennae 3-4 the length of the 

 body with short hairs. Thorax and abdomen dusky; legs pale 

 spurs short. Wings hyaline; venation similar in both the short 

 and long winged forms (Figs. 262, 264). Hypopygium pubes- 

 cent, claspers simple (Eig. 136). Halteres long, knob dark, 

 pedicel pale at base. 



Female. Length i to 2 mm. Color lighter than the male. 

 Head dark, antennae about as long as the head and thorax. 

 Ovipositor like that of Sciara, terminal joint oval. 



Dr. Hopkins reared this species in West Virginia from scabby 

 and diseased potato tubers. He also observed the larvas feeding 

 on the healthy living tissue of the potato and states that they 

 cause conditions wdiich in one stage would be recognized as 

 ])otato scab and in a more advanced stage be recognized as a 

 form of potato rot. 



Specimens of this species were submitted to me for exami- 

 nation by Professor H. A. Surface Avho stated that the larvae 

 were found in Pennsylvania injuring peony bulbs. I have also 

 seen specimens from Rhinebeck, N. Y., and from Columbia, 

 Mo., which were collected by Prof. C. R. Crosby in rubbish 

 while sifting for spiders. 



4. Genus Trichosia Winnertz. 



Monogr. Sciarinen. 173, 1867. 



In structural characters similar to the genus Sciara, but 



differs in having the wing surface distinctly hairy instead of 

 microscopic setulose. 



Trichosia hehes Loew. 



Berlin. Ent. Zeitschr. XIII. 161. 1869. 

 Female. Length 2.9 mm., wing 2.6 mm. Black including 

 head; face, palpi, and antennas fuscous black, the base of the 

 last paler. Mesonotum moderately shining, humeri yellowish. 



