896 Charles Paul Alexander 



Limnobia is a rather small genus of usually handsome flies, including 

 about thirty-five described species. The species are most numerous in 

 Europe and North America, but a very few range into the tropics of 

 both hemispheres. Most of the crane-flies described as species of Limnobia 

 before the partition of the genus, do not belong here at all. 



The haunts of the immature stages, so far as known, include a con- 

 siderable range of habitats, from possibly aquatic forms (L. parietina) 

 to those living in moist earth near streams (L. fallax and probably L. 

 solitaria), in decaying vegetable matter (L. indigena, according to Greene), 

 in decaying leaves (L. nigropundata, L. Jlavipes, L. tripunctata) , in rotten 

 wood (L. cinctipes, L. annulus, L. dumetorum, and others), and in fungi 

 (L. triocellata, L. xanthoptera, and often L. cinctipes and L. annulus). 



The local species of Limnobia may be separated according to the fol- 

 lowing key: 



1. Cross-vein r at the tip of 72i 2 



Cross-vein r removed from the tip oi Ri 7 



2. Knob of the halteres black 3 



Knob of the halteres pale at the apex 6 



3. Femora yellow, the extreme tips narrowly dark brown; wings yellowish, with three eye- 



like markings. [Proc. Acad. Nat. Sci. Phila., p. 216. 1859.] (Plate XXXII, 34.) 



L. triocellata O. S. 



Femora with one or more dark brown rings before the dark tips; wings without an ocellate 



pattern 4 



4. Wings with four large dark brown spots in cell R that are about equidistantly spaced. 



[Proc. Acad. Nat. Sci. Phila., p. 289. 1861.] L. hudsonica O. S. 



Wings not with four large brown equidistant spots in cell R .5 



5. Small, wing of female about 9.5 mm.; wings narrow, with a distinct dark brown pattern; 



spots in cell R small, clear-cut, dark brown. [Proc. Boston Soc. Nat. Hist., vol. 34, 



p. 125. 1909.] (Plate XXXII, 32.) L. fallax Johns. 



Larger, wing of female about 11 mm.; wings broader, with the pattern paler brown, more 

 diffused; spots in cell R larger, often poorly defined and sometimes confluent, medium 

 brown. [Proc. Acad. Nat. Sci. Phila., p. 215, pi. 3, fig. 6. 1859.] (Plate XXXII, 31.) 



L. solitaria O. S. 



6. Femora with three brown bands. [Proc. Acad. Nat. Sci. Phila., p. 214. 1859.] 



L. immatura O. S. 



Femora with two brown bands. [Journ. Acad. Nat. Sci. Phila., vol. 3, p. 21. 1823.] 



(Plate XXXII, 29.) L. cinctipes Say 



7. Wings with brown clouds and seams 8 



Wings nearly clear, at most with three or four small brown dots along the costal 



margin 9 



8. Large species, wing 15 mm.; wing apex very blunt; all the cells clouded and marbled 



medially with gray and brown. [Proc. Acad. Nat. Sci. Phila., p. 289. 1861.] (Plate 



XXXII, 30.) L. -parietina 0. S. 



Small species, wing under 12 mm.; wing apex normal; apical cell with the markings con- 

 fined to the region near the veins. [Proc. Acad. Nat. Sci. Phila., p. 215, pi. 3, fig. 3. 

 1859.] (Plate XXXII, 33.) L. indigena O. S. 



