1914.] NATURAL SCIENCES OF PHILADELPHIA. 593 



light brown, rather darker medially; scutelluin more yellow me- 

 dially; postnotum gray. Pleurae dull light yellow with a broad dark 

 brown stripe extending from the cervical sclerites to the postnotum; 

 mesosternum suffused with brown. Halteres light yellow, the 

 knobs darker. Legs, coxse and trochanters dull yellow, femora 

 brownish yellow, tibiie similar, the tip narrowly brown, tarsi brown. 

 Wings subhj'aline, stigma indistinct, veins brown; venation (PI. 

 XXV, fig. 3)^. 



Abdominal tergites dark brown, sternites much paler, yellowish 

 white, hypopygium brown. 



Holotype, d", Sacandaga Park, Fulton Co., N. Y., June 20, 1910. 



Allotype, 9 , topotypic. 



Parat^^pes, 50 cf 9 , topotypic; Mountain Lake, Fulton Co., X. Y., 

 alt. 1,580 feet, June 15, 1914; Orono, Penobscot Co., Me., July 29, 

 1913; Ithaca, Tompkins Co., N. Y., July 7, 1911; Ridgewood, 

 Bergen Co., N. J. 



A common and widely distributed species in the Eastern United 

 States; the material has been compared with the types of contempta 

 in the Museum of Comparative Zoology, and the form differs as 

 described above. The species has been in the collection of Mr. 

 Leonard and myself for some years. 



A key to the species of the luteipennis group in the Eastern United 

 States. 



1. Cell Ml absent noveboracensis Alex.^ 



Cell Ml present 2. 



2. Wings wdth small brown dots on the cross-veins and at the forks, 



luteipennia O. S.^ 

 Wings clear, unspotted ; 3. 



3. Thorax clear Vjlue-gray inornata O. S.'^ 



Thorax brownish without gray color 4. 



4. Larger species with the pleurae unmarked contempta 0. S.* 



Smaller species; pleurae with a conspicuous dark brown stripe 



from the cervical sclerites to the postnotum, 



mgripleura A. & L., sp. n. 



The members of the luteipennis group have the following characters 

 in common: head narrow and prolonged behind; pronounced 

 pseudosutural or humeral pits; conspicuous tuberculate pits on 

 either side of the middle line of the praescutum in front. Venation 



^noveboracensis Alexander; Pysche, vol. 18, pp. 196 to 198; 1911. 

 '^luteipennis Osten Sacken; Proc. Acad. Nat. Sci. Phila., p. 2.36; 18.59. 

 Hnornata Osten Sacken; Mon. Dipt. N. Am., vol. 4, pp. 219, 220; 1869. 

 « contempta Osten Sacken; I.e., pp. 218, 219; 1869. 



