1008 CHARLES PAUL ALEXANDER 



Tipula usitata Doane 



1901 Tipula usitata Doane. Journ. N. Y. Ent. Soc., vol. 9, p. 124. 



A large number of fully grown larvae of an unknown species of Tipula 

 were found beneath the bark of a fallen tree at Stanford University, 

 California, on March 22, 1915, by Harold Morrison. They were sent 

 to the writer at Ithaca, New York, and emerged as adults on April 15. 

 The immature stages are very distinct, closest perhaps to T. trivittata, 

 which also lives beneath the bark of decaying trees. Nothing is known 

 of the habits of the adult flies. 



Larva. Length, 25-27 mm. 

 Diameter, 3-3.2 mm. 



Coloration pale greenish yellow, darker above. 



Form terete. Body with a very sparse pubescence. Chaetotaxy as follows: tergites 

 (Plate XCV, 527) with a posterior row of eight setae, the middle pair of each side very closely 

 approximated; a seta near lateral margin at base of posterior ring, on a level with pleural 

 seta; pleurites, one seta on each ring; sternites with eight setae in closely approximated pairs 

 on posterior ring. Spiracular disk (Plate XCV, 528) surrounded by six lobes; dorsal and 

 lateral pairs slender, tips of former acute; ventral lobes blunt; ventral lobes with tips black- 

 ened, continued down proximal margin of lobes as a paler brown line; lateral lobes with inner 

 face narrowly blackened, this mark not reaching spiracles; dorsal lobes with entire inner face 

 bulging, intensely black, the marks contiguous at their basal inner angle; an indistinct brown 

 spot underneath each spiracle, in some specimens this mark continuous with that of ventral 

 lobes; lobes not fringed with hairs. Spiracles large, separated by a distance about equal to, 

 or a little greater than, diameter of one. Anal gills short and blunt, strongly protuberant, 

 surrounding anus as four fleshy lobes (Plate XCII, 510). 



Head capsule as in genus. Mentum broad, with seven to nine teeth, in the latter case 

 the outermost pair very small. Hypopharynx with three or five very blunt teeth. Antenna 

 much shorter and stouter than in most species of Tipula, the length only a little greater than 

 twice the diameter, at apex with a blunt conical papilla and a few small, cylindrical sense 

 pegs. Mandible powerful, with two or three flattened teeth on ventral cutting edge. 



Pupa. Length, 15-16.8 mm. 

 Width, d.-s., 2 mm. 

 Depth, d.-v., 2.3-2.4 mm. 



Coloration pale brown; posterior margin of abdominal rings pale; lateral margin of 

 abdomen conspicuously pale yellowish white. 



Form slender. Pronotal breathing horns narrow, a little expanded at tips. Leg sheaths 

 ending on a level. 



Abdominal spines very strong, but few in number; tergites with four to six spines; pleurites 

 with a single weak spine on each ring; sternal spines very strong, five or six in number, those 

 on segment 7 subequal in size to those on segment 8; no sternal spines on base of posterior 

 ring. Male cauda with posterior dorsal lobe very strong, pale, tips acute; lateral lobes greatly 



