208 Illinois State Laboratory of Natural History. 



PiipcB [Fig. 34]. — Color dark brown or black, cylin- 

 drical, slightly tapering behind, the surface more or less 

 finely transversely wrinkled. The base of each antenna 

 bears a small tooth or angulation, and a pair of small 

 teeth lie between them. The prothoracic respiratory 

 tubes are rather distant at base, divergent, and not more 

 than twice as long as the distance separating them. 

 They are finely ringed and are knobbed at tip, with an 

 apical vertical slit, apparently closed by a membrane. 

 Between the tubes the prothorax at middle is carinate. 

 The mesothorax bears a small tubercle behind each re- 

 spiratory tube, and a more acute pair at middle of disk 

 above. The wing-pads attain the apex of the second 

 abdominal segment. All six tarsi lie side by side on the 

 breast, nearly or quite exactly in line, and attaining 

 apex of third abdominal. 



The abdominal segments are proportioned about as in 

 the larvae, segments 2-7 being double. Each bears near 

 its posterior margin a row of short thick spines. The 

 lateral margin is narrow and prominent, and also spined. 

 The last two segments are closely united, the last one 

 bearing four spiny teeth above, and a prominent large 

 pair behind these. The end in the female is conical and 

 pointed, being apparently composed of three united 

 slender tapering prolongations, two above and a broader 

 deeply bifid one below. In the male the end is thick and 

 more or less truncate, each side bearing three small 

 tubercles or teeth 



KEY TO LARV^ OF TIPULIN^. 



Anal prominence bearing six finger-like appendages. 

 Stigmatal teeth six, broad, rather short, about 

 equal. [Fig. 33.] 

 One or two irregular stripes of brown pubescence 



each side of back. Aquatic Tipula eluta. 



Back not striped with pubescence. Terrestrial. 



Tipula Mcornis.*' 



♦Sixteenth Rep. State Ent. 111., p. 78. 



