366 CONXECTICUT GEOL. AND NAT. HIST. SURVEY [Bllll. 



8. Wings with m-cu at or close to fork of M; anterior arculus lacking ( Fij;. 



43, D) (Dactylolabaria) Dactylolabis 



Wings witli ;;;-(•;( beyond the fork of I\I, at from one-third to one-half the 

 length of the cell 1st Mj-. where close to fork of M (some PseiidolUuno- 

 f'liila ) , the arculus complete 9 



9. Wings with the anterior arculus lacking (Fig. 43, E-G) (Pseudolimno- 



philaria, part) . . . 10 



Wings with the anterior arculus present (Fig. 43, H-P) II 



10. Cell Isf M-2 of wings very large, its inner end lying far proximad of the 



other elements of the cord (Fig. 43, E) Prolimnophila 



Cell 1st M> of wings of normal size, its inner end straight and in approxi- 

 mate alignment with the elements of the anterior cord (Fig. 43, I*", (j ) 



Austrolimnophila 



11. Wings with Sc relatively short, Sci ending before the level of the fork of 



Rs (F'ig. 44, F-H) (Limnophilaria, part); compare also Liiiuiopliila 



alhipcs, F'ig. 44, C, readily separated by the white posterior tarsi 12 



Wings with Sc longer, Sci ending opposite or beyond the level of the fork 

 of Rs (Figs. 43, H, I; 44, D, E) ; compare also Pilaria rccondita. distin- 

 guished by the elongate antennal verticils 13 



12. Antennae with long, conspicuous verticils; tuberculate pits present, small, 



placed at extreme cephalic end of praescutum ; Rs elongate, exceeding vein 



R^; cell Ml present or lacking (Fig. 44, G, H) Pilaria 



Antennae with short verticils ; tuberculate pits lacking ; Rs short and 

 strongly arcuated or angulated at origin; cell Mi lacking (Fig. 44, F) 



Shannonomyia 



13. Head strongly narrowed and prolonged behind; radial and medial veins 



beyond cord long and sinuous ; vein R^ extending generally parallel to vein 

 Ri, not diverging markedly at tips ; vein 2nd A strongly curved to margin 



(Fig. 43, H, I). (Pseudolimnophilaria, part) Pseudolimnophila37 V 



Head broad, not conspicuously narrow ed behind ; radial and medial veins 

 more nearly straight ; vein Rs diverging strongly from vein Ri ; cell Rx 

 conspicuously widened at margin ; vein 2)id A not curved strongly into 

 margin (Fig. 44, A-C). (Limnophilaria, part) Limnophila ^'' 



1. Siibtribe Oxydiscaria 



Oxydiscus de Meijere 



1891. Adelphonii/ia of autjiorities, nee Bergroth, Mittheil. Xaturf. 



Ges. Bern, 1890 : 134. 

 1913. Oxydiscus de Meijere; Tijd. voor Ent., 56:350. 



The genus Oxydiscus is placed in the present tribe with some ques- 

 tion. On the basis of structure of the adult, the species of the genus 

 are hexatomine and are the smallest species of the tribe within our 

 faunal limits. The larvae of this genus show certain features held 

 as being characteristic of the tribe Pediciini and the group had earlier 

 been placed in this latter tribe in treatments by the present writer. 

 The immature stages occur in rich saturated organic earth. 



Key to Species 



1. Wings with cell Mx lacking (Fig. 43. B ) cayuga 



Wings with cell M, present (Fig. 43, A) 2 



2. Coloration of body and wings clear light yellow; macrotrichia of wing-cells 



very restricted in number and area, occurring in the extreme outer cells only 



minutus 

 Coloration of thoracic notum brownish yellow to dark brown ; wings tinged 

 with gray or brown ; macrotrichia of wing-cells more abundant, occurring 

 in cells distad of level of vein R-2 3 



