906 CHARLES PAUL ALEXANDER 



these areas near base of segments. Female cauda (Plate LXIII, 334) with tergal valves 

 elongate, tapering gradually to the rather blunt tips; sternal valves very small, blunt at tips; 

 at base, on dorsal side of eighth segment, two setiferous tubercles. 



Nepionotype Larch Meadows, Ithaca, New York, May 15, 1917. No. 52-1917. 

 Neanotype. Ithaca, May 27, 1917, a cast pupal skin. 



Group Dicranotae 



Genus Dicranota Zetterstedt (Gr. a fork) 



1838 Dicranota Zett. Ins. Lapponica, Dipt., p. 851, no. 164. 



Dicranota is a small genus of crane-flies (about fifteen described species) 

 occurring thruout the Holarctic region. Four species are found in eastern 

 North America. None of the American species have been reared. In 

 Europe, the life history and morphology of Dicranota bimaculata (Schum.) 

 has been discussed in detail by Miall (1893) and by Wesenberg-Lund 

 (1915:342-343). Larvae were found by Miall in numbers in the muddy 

 banks of small streams and ponds, where they bury themselves in the 

 mud and gravel. They creep about with ease and rapidity between the- 

 sancl and gravel, and are able to swim well by a looping movement. Their 

 food consists largely of small worms, Tubifex rivulorum Lam., which 

 abound in these haunts. The pupal stage is passed in damp earth. The 

 larva is stated to be about 18 millimeters in length,' but this seems to be 

 a maximum figure. The body is dirty white in color and is covered with 

 fine, appressed hairs. Abdominal segments 3 to 7 bear paired retractile 

 pseudopods, which are circled with three rows of chitinized hooks gradually 

 decreasing in size from the tips inward. The anal gills, four in number, 

 are distinctly segmented. The head capsule is elongate and massive, 

 as in the tribe. The mentum is completely divided, its anterior margin 

 having the usual six teeth. The mandible is of the usual pediciine type, 

 with acute teeth on the ventral cutting edge and a brush of hairs near 

 the prosthecal region. (Plate LXIV.) 



The pupa is small, only about 10 millimeters in length, and has the 

 pronotal breathing horns expanded and flattened at the tips. The dorsal 

 surface of the abdomen is provided with roughened plates armed with 

 rather strong and dense spines, there being one such plate on the third 

 segment, two on the fourth to sixth segments, and one on the seventh 

 segment. 



