902 Charles Paul Alexander 



7. Rs long, normal in position; cell Isl Ri elongated 8 



Rs shortened, its first fork with vein 7^2 +3 at an angle to the end of the sector so that 



cell Ul Ri is equilateral or nearly so Cryptolabis O. S. (p. 906) 



8. Rs ending in cell Ri Molophilus Curt. (p. 906) 



Rs ending in cell R3 9 



9. A supernumerary cross-vein in cell Ri; second anal vein strongly bisinuate. 



Helobia St. Farg. (p. 907) 

 No supernumerary cross-vein in cell ^2; second anal vein not bisinuate 10 



10. Cui tending to turn toward the wing apex; forks of the longitudinal veins very long 



and deep Erioptera Meig. (p. 908) 



Cwi straight or tending to turn away from the wing apex 11 



11. Sides of the long cell tst M2 parallel; 1SV2 not far removed from the tip of -S>i; coloration 



of the local species black; basal deflection of C'wi beneath the middle of cell 1st M-2. 



Gnophomyia O. S. (p. 909) 



Sides of cell 1st Mi more or less divergent distad; Sd retreated toward the wing base 



so that Sci is usually more than two-thirds the length of the sector. .' 12 



12. Deflection of Ciii meeting M far before the fork of the latter; Rs long and straight at its 



origin; the terminal three segments of the antennae abruptly smaller than the other 



segments of the flageUum; wings glabrous Trimicra 0. S. (p. 910) 



Deflection of Cui meeting M usually at the fork or on M3+4 underneath cell 1st M^; 

 Rs shorter, tho straight; flagellar segments of the antennae gradually and uniformly 

 smaller toward the tip of the organ; wings pubescent Ormosia Rond. (p. 911) 



Genus Chionea Dalman 



1816 Chionea Dalman. K. Vet. Akad. Handl., vol. 1, p. 102. 



Chionea is a peculiar genus of subapterous crane-flies. There are 

 about five European and six American species so far described. The 

 possible evolution of the group from winged ancestors (Pterochionea 

 Alex., Crypteria Berg.) has been discussed by the author in another 

 paper (Alexander, 1916:529-530). 



The immature stages of the known species are spent in the soil. The 

 adult flies are usually found crawhng about on the snow, being more 

 conspicuous when snow is on the ground than at other seasons. In the 

 spring and fall they are occasionally found in leaf mold. An interesting 

 paper on the genus has been written by Johnson (1907). Dr. Dietz has 

 in his collection a female specimen which was taken at Aweme, Manitoba, 

 in September, when the temperature was below zero. 



All the earlier authors describe this fly as being wingless. This is not 

 exactly true, however, the wings being present tho reduced to mere knobs, 

 much smaller than the halteres. The generalized species have the normal 

 number of antennal segments for this tribe of flies, this being sixteen — 

 the two scapal segments, a basal fusion segment of the flagellum made 

 up of five segments, and nine free flagellar segments beyond. In the 



