SUMMARY OF FOOD HABITS OF AMERICAN GALL MIDGES. 



By E. P. Felt, 



Albany, N. Y. 



Our understanding of this group will be much clearer if 

 we recall that it is an offshoot from the Mycetophilidae, the 

 species of which subsist largely upon decaying vegetable matter 

 or low forms of vegetable life. The family Itonidae, better 

 known as the Cecidomyiidae, has attained its present large 

 proportions not by reason of strength, great resistant powers 

 or unusual fecundity, but through an amazing adaptability. 

 We find larvae in decaying vegetable matter, in dead wood, on 

 fungus, affecting all parts of a very great variety of the higher 

 plants and presenting thereupon almost every conceivable 

 grade in the development of the gall, living as parasites at the 

 expense of very small insects or even preying upon their near 

 allies. Broadly speaking, taxonomic studies in this family 

 show at least a moderately close relationship between speciali- 

 zation in structure and divergence in the food habits from those 

 of ancestral forms. 



We have no firsthand knowledge of the food habits of the 

 tribe Lestremiinariae, though there is every reason to believe 

 that there is substantial agreement in this regard with Euro- 

 pean species, which have been reared from decaying 

 vegetable matter. 



We can supply a little definite information respecting the 

 food habits of the tribe Campylomyzariae, since representatives 

 of several genera have been reared. Mycophila fungicola, an 

 undescribed species, referable to a new genus was reared from 

 fungus, while Monardia lignivora Felt was obtained in consid- 

 erable numbers from the fungous-affected heartwood of white 

 pine. Cordylomyia coprophila is an undescribed species refer- 

 able to a genus which will be erected shortly. It was reared 

 from manure. These few records show that this compara- 

 tively generalized tribe subsists upon fungi , fungous-affected wood 

 and certain forms of vegetable matter. These food habits agree 

 in general with those of European species, and further observa- 

 tions will doubtless show that members of the tribe as a whole, 

 depend for nourishment on the lower plants or upon the tissues 



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