522 PROCEEDINGS OF THE ACADEMY OF [Oct., 



appendage (3) a slender, fleshy rod, beyond the slightly enlarged 

 base bent strongly dorsad so that it lies above the second appendage, 

 directed caudad at the tip which is capped by a short, blunt, chitinized 

 spine. Ninth tergite short, broad, the caudal margin transverse. 

 Ninth sternite with a prominent median knob on the caudal margin,, 

 provided with numerous setigerous tubercles. 



Gonomyia (Gonomyia") cognatella Osten Sacken. 



Gonomyia cognatella Osten Sacken; Proceedings of The Academy of Natural 

 Sciences of Philadelphia, p. 230 (1859). 



A more southern species than the last, their ranges overlapping 

 in New York State : 



Connecticut, New Haven County, East River, July 6, 1910 (Ely). 



New York, Fulton County, Sport Island, Sacandaga River, June 

 18, 1911, to August 26, 1916 (Alexander); Herkimer County, Indian 

 Castle, June 10 to 13, 1915 (Alexander). 



Maryland, Montgomery County, Cabin John Bridge, May 16, 1909 

 (Knab); Plummers Island, May 24, 1914 (McAtee). 



District of Columbia, Washington (Osten Sacken) ; the type-locality. 



Virginia, Fairfax County, Difficult Run, July 25, 1915 (McAtee 

 and Alexander). 



North Carolina, Buncombe County, Black Mountains, July 16, 

 1912 (Beutenmuller). 



The wing is shown on Plate XXVI, fig. 29. 



The male hypopygium (Plate XXIX, figs. 73-75) with the pleurites 

 very short and stout, the inner dorsal angle produced caudad as a 

 slender, finger-like lobe, fimbriate with eight or nine long stout hairs 

 on the dorsal inner edge; at the base of the lobe a small, slender, 

 cylindrical knob (k) with three long hairs at the apex; ventrad of 

 this finger-like angle of the pleurite is an elongate, very slender, pale 

 appendage (2) directed caudad and slightly ventrad and proximad, 

 at the apex with two long slender hairs ; pleural appendage (3) directed 

 ventrad on its basal portion, soon bent directly upon itself, dorsad, 

 the tip caudad; the appendage is pale, chitinized, slender, bifid, the 

 lateral arm with the apex somewhat twisted, the proximal arm a 

 slender, pale stylet directed strongly proximad, at the apex with an 

 elongate, slender, black, chitinized spine. Proximad of the base 

 of the knob (fc) is a slender appendage with a prominent hair at the 

 apex and two slightly smaller subterminal hairs. 



