Weiss — Diptera and Fungi. 87 



In the subfamily Sciarinae, Sciara multiseta Felt has been reared from 

 mushrooms and Sciara agraria Felt is recorded as being numerous at times 

 in mushroom cellars. Definite information concerning the exact identity 

 of the hosts of most of the Mycetophilidae is lacking although it is quite 

 possible that almost any agaric or bolete will suit the tastes of many of 

 these flies. 



In the Itonididae, Dr. E. P. Felt has called my attention to the fungus 

 and related habits of several species as recorded in several of his reports.^ 

 The more or less strictly fungous species were listed by Dr. Felt in his paper 

 on "Hosts and Galls of American Gall Midges*" and these are presented 

 as follows : 



Host Species 



Fungus on rotting plum Hyperdiplosis fungicola Felt. 



Unknown fungus Arthrocnodax macrofila Felt. 



Aecidiospores of Uromyces pisi Toxomyia rubida Felt. 



Teleutospores of Puccinia Toxomyia fungicola Felt. 



Young mushrooms Mycophila fungicola Felt. 



Reared from Oecidium impatientis Mycodiplosis impatientis Felt. 



Larvae on Oecidium importatum affect- 

 ing Peltandra sp. Mycodiplosis sp. 



Under hard, black carbonaceous fungus 



on decayed oak stump Lasiopteryx flavotibialis Felt. 



Fungus affected heartwood of pine Monardia lignivora Felt. 



Large yellowish fungus on rotten bark Mycodiplosis fungiperda Felt.^ 



Of particular interest are the species of Toxomyia and Mycodiplosis 

 which were reared from the spores of the rusts and smut. Many other 

 species of Itonididae are mentioned by Dr. Felt as having been bred from 

 decaying bark and wood and it is extremely probable that these may be 

 more or less closely associated with the fungous hyphae which usually 

 penetrate such objects. 



In connection with Diptera and fungi, it is of interest to note the peculiar 

 fungoid growth or development of the tissues which accompanies the 

 activities of Asteromyia larvae in the leaves of Solidago. Writing about 

 Asteromyia carbonifera Felt, the oval, blister-like gall of which is common 

 upon the leaves of the narrow leaved Solidago graminifolia, Felt* states 

 that "the characteristic blister galls produced by this and allied forms 

 are usually filled, or nearly so, with a black carbonaceous matter, suggest- 

 ing that the tissues may have become badly infected by fungus. This 

 material is almost invariably present in many galls. Professor Peck states 

 that after repeated examinations, he has failed to observe any evidence of 

 the characteristic fruiting bodies of fungus, and consequently we must 

 assume this malformation to be independent of fungus infection and 

 produced by the activities of the larva. Doctor Trelease, writing in 1884, 



IN. Y. St. Mus. Bui. 165, 175. 180, 198, 202. 

 2Jour. Econ. Ent. vol. 4, No. 5, p. 461. 

 3N. Y. St. Mus. Bui. 202, p. 196. 

 ♦N. Y. St. Mus. Bui. 198, p. 209. 



