1915.] NATURAL SCIENCES OF PHILADELPHIA. 487 



The insect was common on June 5, 1913, in a woody tract along 

 the Stillwater Bayou, Orono, Me., where it occurred with Dicranomyia 

 liberta, Erioptera caloptera, E. armata, and Tipula hella. 



The fly was reared from a large aquatic larva found in the Indian 

 Spring near Ithaca, Cayuga Lake, N. Y., where it occurred in the 

 beds of water-cress (Radicula nasturtiimi-aquaticum) in company of 

 other Tipulid larvse, such as Pedicia alhovitta, LimnophUa quadrata, 

 Tipula ahdominalis and T. hella, as well as a host of the usual aquatic 

 organisms. Other larvse of this species, likewise strictly aquatic, 

 were found in Coy Glen, Ithaca, N. Y., a rapid-flowing gorge stream. 



Tipula triton sp. n. 



Coloration light yellow; antennae bicolorous; thoracic stripes 

 reddish brown; abdomen with a series of about four conspicuous 

 rounded brown spots along the sides; male hypopygium with the 

 ninth tergite trifid; penis-guard subtended by two very large blade- 

 like appendages which are drawn out apically into sharp points. 



3/afe.— Length, 1.3.2-13.5 mm.; wing, 13.5-13.6 mm. 



Frontal prolongation of the head rather long and slender, brownish 

 yellow, the nasus distinct; palpi short, brown. Antennae moderately 

 long, the three basal segments dull yellow, the remaining segments 

 of the flagellum with a distinct dark brown basal enlargement, the 

 apex of the segments brownish yellow, on the terminal three or four 

 segments more bro'vvnish. Head pale yellowish gray with an indis- 

 tinct brownish subimpressed median line. 



Thoracic dorsum light yellow with three indistinct light reddish 

 brown stripes of which the median one is bisected by a narrow 

 median ground vitta; the lateral praescutal stripes begin immediately 

 behind the prominent pseudosutural foveae; scutum dull light yellow, 

 each lobe with two reddish brown spots which are approximated; 

 scutellum and postnotum dull light yellow. Pleura yellowish, 

 heavily whitish pollinose. Halteres rather short, the stem yellowish, 

 the knob brown. Legs with the coxae yellowish, whitish pollinose; 

 trochanters yellow; femora yellow, the apex narrowly brown; tibiae 

 yellowish brown, the apex narrowly and very indistinctly^ darker; 

 tarsi dark brown. Wings subhyaline with a faint brownish tinge, 

 the costal cell more yello\\dsh; the stigma large, light brown, indis- 

 tinct; a narrow vitreous band before the stigma extending along 

 the cord into cell 1st M^. Venation as in Plate XVI, fig. 11. 



Abdominal tergites brownish yellow, the segments six and seven 

 dark brown; eight yellowish, the ninth reddish; the apices of the 

 segments are very narrowly ringed with silvery; on segments three 



