1914.] NATURAL SCIENCES OK I'lIlLADELl'Ill A. .')97 



1. Mcsouotuni ami plcurii' yellowish or hrownish yellow; wings ]):ilc 



yellow; size small .stdnirovda; si), ii. 



Mesonotuin and pleura' not yellow; size larf^er 2. 



2. PleuriP and niesonotuni clear bluish black with a graj' blot)ni, only 



the coxa^ conspicuously light yellow; wings with a yc.'llowish 

 tinge; cross-vein r beyond the fork of liin on li^, 



quadrata (). S.'^ 



Pleurae with a conspicuous black dorsal stripe; niesonotuni rich 



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



of /?2+j osborni sp. n. 



The members of the qiuidrata group have the radial sector long 

 and in a line with R:+s; cells R,, Ki and 1st Mi in a line or nearly so; 

 cell .U, absent. 

 Limnophila emmelina sp. n. 



Brown, abdomen hairy; wings brown; cell H^ sessile; cell M, 

 absent. 



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



Rostrum very short, reddish brown, the pali)i brown. Antenna:' 

 rather short, dull yellowish brown. Head reddish brown. 



Thoracic dorsum yellowish brown without distinct darker mark- 

 ings. Pleura; dull yellow. Halteres yellow. Legs, co.xa; and 

 trochanters dull j-ellow, 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 brown; venation (PI. XXVII, fig. 28): 

 7?.. arising from the sector so that the cell Hz is sessile; cell .17, 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 Ii;. 



Tribe Pedicini. 



Genus ORNITHODES Coquillott. 

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

 Ornithodes harrimani Coquillett. 



1900. Ornilhodes harrimani Coquillett; Proceed in{!?< 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 ^■i^gin's Bay, Alaska, June 26, 1899. This insect is 

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



'^(juadrala Osten Sacken; Proc. Acad. Nal. Sci. Phita., p. 241; 1S.5'.); Mc 

 Dipt. N. Am., vol. 4, p. 230; 1S69. 



