86 Proceedings of the Biological Society of Washington. 



to him, a large number of wild mushrooms are infested with the larvae of 

 Mycetophilinae, particularly of the genera Exechia and Mycetophila. In 

 several instances they were found with Phora larvae in numbers sufficient 

 to ruin a cultivated mushroom bed. Most of the following information 

 concerning Mycetophilidae has been compiled and tabulated from Johann- 

 sen's monograph. In the case of subfamilies not mentioned, no definite 

 information was given. 



Subfamily Ceroplatinae 

 " Sciophilinae 



" Mycetophilinae 



" Sciarinae 



Larvae in rotten wood and in fungi. 



Larvae in rotten wood and in fungi. 



Larvae in rotten wood and in fungi. 



Members occasionally reported as injuring 

 mushrooms. After partial decay of fungus 

 growths, Sciara larvae found in numbers 

 and this has led mushroom growers to 

 attribute the destruction to these gnats, 

 when damage was probably done by species 

 of Mycetophila, Exechia or Phorids. 



In the Sciophilinae the genera Tetragoneura, Sciophila and Mycoma are 

 mentioned as living in rotten wood and in fungi during their larval stages 

 and Winnertz is recorded as rearing Mycoma from Daedalea quercina and 

 Polyporus and Sciophilae from Hydnu?n repandum, Boletus scaber and 

 Daedalea quercina. The last mentioned fungus is a Polypore which is 

 rarely attacked by insects probably on account of its corky and conse- 

 quently unpalatable context and it is quite likely that the above men- 

 tioned rearings were made from sporophores which were in an advanced 

 stage of decay. According to Osten Sacken, the larvae of Sciophila live 

 on the surface of the fungus which they cover with a web and do not burrow 

 inside. 



In the Mycetophilinae, the activities of the genera and species appear to 

 be definitely known as follows. 



Genus Leia 

 " Cordyla 

 " Rhymosia 



" Exechia 



Mycothera 

 Mycetophila 



Sceptonia 

 Zygomyia 



Larvae in mushrooms. 



Larvae in decaying wood and in fungi. 



Larvae in fungi (Armillaria, etc.) R. inflala Joh. bred 

 from Armillaria mellea. 



Larvae frequently in wild mushrooms, occasionally 

 in cultivated ones. E. cincinnata Joh., reared 

 from Boletus granulatus. E. saiiata Joh., from 

 shelving mushroom. E. nativa Joh., from Collybia 

 sp. E. absoluta Joh., from Boletus granulatus. 

 E. capillata Joh., from Collybia dryophila. 



Larvae in decaying wood and in fungi. 



Larvae frequently in wild mushrooms, sometimes in 

 cultivated ones. M. scalaris Loew, reared from 

 Boletus and Polyporus. M. foecunda Joh., from 

 Polyporus sp. M. lenta Joh., from mushrooms. 



Larvae in decaying wood and in fungi. 



Larvae in decaying wood and in fungi. 



