6 PEOCEEDINGS OF THE NATIONAL MUSEUM vol.68 



narrowly yellowish; hypopygium with the tergite and basistyles 

 infuscated. Male hypopygium (fig. 1) with the ninth tergite nearly 

 transverse, the median area very slightly produced into a low, 

 dark tubercle. Basistyles small, the mesal lobe very large, the apex 

 blackened and set with numerous setigerous tubercles. Ventral dis- 

 tistyle moderately fleshy with a long slender rostrum (fig. IB) that 

 bears at its tip a slender spinous seta and a few more delicate bristles; 

 two relatively short spines, placed less than their own length apart 

 and not far from the base of the rostrum. Dorsal dististyle a very 

 strongly curved chitinized rod, the base stout, the apex beyond the 

 approximately rectangular curve narrowed, feebly dilated before the 

 acute straight apex. Gonapophyses with the mesal apical angle of 

 each produced caudad into a dusky nearly straight lobe. Aedeagus 

 stout. 



Described from a single male, collected at Amagu Village, Siberia, 

 July 1923 (T. D. A. Cockerell). 



Type.— Male, Cat. No. 28358, U.S.N.M. 



DICRANOMYIA, species, near PSEUDOMORIO Alexander 



1920. Dicranomyia pseudomorio Alexander, Trans. Amer. Ent. Soc, vol. 

 46, pp. 3-4. 



One badly damaged specimen that probably belongs here, Kudia 

 River, Amagu, Siberia, July 1923 (T. D. A. Cockerell). 



Genus RHIPIDIA Meigeit 



1818. Rhipidia Meigen, Syst. Beschr. Zweifl. Ins., vol. 1, p. 153. 



RHIPIDIA (RHIPIDIA) MACULATA Meigen 



1818. Rhipidia maculata Meigen, Syst. Beschr. Zweifl. Ins., vol. 1, p. 153, 

 pi. 5, fig. 11. 



One male, Kongaus, Siberia, August 1923 (T. D. A. Cockerell). 

 This fly is distributed throughout the Holarctic region. 



RHIPIDIA (MONORHIPIDIA) SIBIRICA, new species 



General coloration dark; fore legs dark brown, the basal quarter 

 paler; wings with a grayish tinge, the costal cell darker; brown spots 

 and seams at origin of Rs, tip of Sc, along the cord and outer end of 

 cell 1st M^; Sc long, ending beyond midlength of Rs. 



Female. — Length, 7 mm. ; wing, 7.8 mm. 



Rostrum and palpi black. Antennae black throughout, the flagel- 

 lar segments with distinct basal petioles, the inner face of each seg- 

 ment slightly produced. Head dark, discolored. 



Thorax entirely dark-colored, any bloom or pattern that might be 

 normally present destroyed by moisture. Halteres pale, the knobs 

 slightly darkened. Legs with the coxae dark brown, discolored, the 



