210 MAINE AGRICUI^TURAI, EXPERIMENT STATION. I909. 



heartiest thanks. I am also under great obhgations to Pro- 

 fessors W. M. Wheeler, J. M. Aldrich, John Barlow, and 

 Messrs. Wm. Beutenmueller and C. W. Johnson for the loan 

 of their collections, to Mr. D. W. Coquillett in permitting me 

 to study the specimens in the United States National Museum 

 and to Dr. Samuel Henshaw for the privilege of examining 

 the Loew types in the museum at Cambridge, Mass. I desire 

 also to acknowledge my indebtedness to Miss Edith M. Patch 

 of the Agricultural Experiment Station of Maine, and to Dr. 

 Chas. D. Woods, director of the station, for encouragement 

 and aid in making possible the publication of this paper in its 

 present form. 



Of the literature upon the Mycetophilidae which has been of 

 greatest assistance I need only mention here Winnertz's 

 "Pilzmiicken," the "Centuries" of Loew from the Berliner 

 Entomologische Zeitschrift, and the papers of Adams, Aldrich, 

 Coquillett, Dziedzicki, Grzegorzek, Lundstrom, Marshall, 

 Riibsaam'en, Skuse and Williston. 



Characters. 



The fungus-gnats are flies of medium or small size, and more 

 or less mosquito-like in form. They are exceedingly numerous 

 both in num.ber of individuals and in number of species, over 

 fifteen hundred species contained in upward of one hundred 

 genera, having been described from Europe, North America 

 and Australia. Although entomologists have long been 

 familiar with the earlier stages as well as with the adults of 

 several members of this family, our knowledge of the life 

 history is as yet very meagre. In 1864 Baron C. R. von Osten 

 Sacken collected all the published records bearing upon the 

 biology and the structural characters of the larvse and published 

 them together with some observations of his own. This paper 

 was reprinted in 1884 with a few additions. 



The larva is twelve segmented, footless, more or less cylin- 

 drical, slightly tapering, smooth, soft, whitish in color and with 

 a small strongly chitinized head, which is usually brown or 

 black. The antennge are always very minute, almost vestigial. 

 The mouth parts consist of a fleshy labrum, with a chitinized 

 framej flat lamelliform mandibles. Indented or serrate on the 



