66 PROCEEDINGS OF THE NATIONAL MUSEUM vol. loe 



June 29, 1951, R. Namba; 19, July 17, 1951, R. Namba). New 

 Jersey: Newark (1 9 , June 18, 1892). New York: Babylon, Long 

 Island (299, June 25, 1934, Blanton and Borders); Farmingdale, 

 Long Island (2 9 9 , 1 cf , Juno 5, 1935, Blanton and Borders) ; Gowanda 

 (19, June 13, 1913, M. C. Van Duzee); Mosliolu (Id', June 18); 

 Station for Study of Insects, Tuxedo {Id", July 10, 1928, C. H. Cui-ran ; 

 IcT, July 6, 1928, C. H. Curran). North Carolina: (IcT); Black 

 Mts. (19, "VI"); Valley of Black Mts. (299, June 24-30, 1906, 

 W. Beutenmeller) ; Fayetteville (1 9 , early June, 1921, C. S. Brimley) ; 

 Goldsboro (1 9 , July 20, 1946, M. W. Wing); Grimesland (1 9 , May, 

 1919); Raleigh (Icf, June 11, 1924; 1 9 , Aug. 13, 1925; 1 9 , July 12, 

 1927; Icf, Sept. 4, 1925; Id", July 28, 1926, all collected by C. S. 

 Brimley; 19, June 21, 1947, G. S. Fichter; 19, July 5, 1948, "at 

 light," M. W. Wing; 1 9 , early August, C. L. Metcalf); Smokemont, 

 GSMNP (Icf, Aug. 15, 1947, Bullock-R. R. Dreisbach). Ohio: 

 Summit County (Icf^, July 13, 1936; 19, June 16, 1937; 2 9 9, 

 June 19, 1937; Id, June 28, 1937, all collected by Louis J. Lipovsky). 

 Pennsylvania: Fern Rock (Ic^, June 9, 1905; 1 9 , June 29, 1905); 

 Manayunk (19, Id"); Montgomery County (19, July 4, 1892). 

 Tennessee: Ellmiont, GSMNP (399, June 15, 1946, R. R. Dreis- 

 bach; 19, Aug. 11, 1947, Bullock-R. R. Dreisbach); Headquarters, 

 GSMNP (19, Aug. 15, 1947, 1,600 ft., Bullock-R. R. Dreisbach); 

 The Chunneys, GSMNP (1 9 , June 11, 1946). Texas: Kerrville (1 9 , 

 May 30, 1906, F. C. Pratt). Virginia: Great Falls (1 9, June 12, 

 1949, C. W. Sabrosky); Mount Auy (Icr', .July 17, 1941, Olson). 

 District of Columbia (1 9 , F. C. Pratt). (In CSW, UM, USNM, 

 SEC, EU, CU, AMNH, NC, ISC, RRD, GS, and ANfeP.) 



Remarks: This species can be separated from tlie other Rivellia 

 by the absence of the strong humeral setae and presence of posterior 

 dorsocentral setae, and by the yellow front legs, male genitalia, wings, 

 and the usual unicolorous black or dark brown body color. 



This species is named in honor of Mr. George C. Steyskal, who has 

 aided me in the study of Diptera. 



Rivellia boscii Robineau Desvoidy 



Figure 2,a-c 



Rivellia boscii Robineau Desvoidy, 1830, p. 730. — Piersol, 1907, pp. 465-467 (on 

 mating habit). 



Type locality: "La Caroline." (The typo "detruits d6finitive- 

 ment," according to E. Seguy, in litt.) 



Male: Body length about 7.0 mm.; with neat slender appearance. 



Head: Frons reddish brown; upper fronto-orbital plates and ocellar 

 triangle slightlj^ blackened. Face with dorsal one- third pruinose, 



