1914.] NATURAL SCIENCES OF PHILADELPHIA. 597 



1. Mesonotum and pleurae yellowish or brownish yellow; wings pale 



yellow; size small stamooodce sp. n. 



Mesonotum and plcunie not yellow; size larger 2. 



2. Pleurae and mesonotum clear bluish black with a gray bloom, only 



the coxae conspicuously light yellow; wings with a yellowish 

 tinge; cross-vein r beyond the fork of R.+s on R2, 



qiiadrata O. 8.^^ 



Pleurae with a conspicuous black dorsal stripe; mesonotum rich 



brown; wings with a brown tinge; cross-vein r at the fork 



of R-2+3 osborni sp. n. 



The members of the quadrata group have the radial sector long 

 and in a line with Ri+s,' cells R3, Rs and 1st M. in a line or nearly so; 

 cell Ml absent. 

 Limnophila emmelina sp. n. 



Brown, abdomen hairy; wings brown; cell R^ sessile; cell Mi 

 absent. 



Male, length about 7 mm.; wing, 8.9 mm. 



Rostrum very short, reddish brown, the palpi brown. Antennae 

 rather short, dull yellowish brown. Head reddish brown. 



Thoracic dorsum yellowish brown without distinct darker mark- 

 ings. Pleurae dull yellow. Halteres yellow. Legs, coxae and 

 trochanters dull yellow, femora yellow, broadly tipped with brown, 

 tibiae dull yellow, rather narrowly tipped with brown, tarsi brown, the 

 base of the metatarsus a little paler. Wings with a slight brownish 

 tinge, no stigmal spot, veins brow^n; venation (PL XXVII, fig. 28): 

 Ro arising from the sector so that the cell Ri is sessile; cell Mi absent. 



Abdominal tergites dark brown, sternites lighter colored. Holo- 

 type, d'. Great Falls, Va., April 20, 1913 (Fred'k Knab). 



From other members of the genus in which cell Mi is lacking 

 this species is readily distinguished by the sessile cell R2. 



Tribe Pedicini. 

 Genus ORNITHODES Coquillett. 

 1900. Ornithodes Coquillett; Proc. Wash. Acad. Sci., vol. 2, p. 400. 

 Ornithodes harrimani Coquillett. 



1900. Ornithodes harrimani Coquillett; Proceedings of the Washington 

 Academy of Science, vol. 2, p. 400. 



The type is No. 5,203 in the U. S. National Museum. It is a 

 male from Virgin's Bay, Alaska, June 26, 1899. This insect is 

 very similar to Tricyphona in venation, but distinct in the curious 



^^ quadrata Osten Sacken; Proc. Acad. Nat. Sci. Philn., p. 241; 1859; Mon. 

 Dipt. N. Am., vol. 4, p. 230; 1869. 



