1916.] NATURAL SCIENCES OF PHILADELPHIA. 515 



The male has never been described, and this specimen is made the 

 allotype. 



Allotype, cf. — Rostrum and palpi dark brown. Antennae with 

 the basal segments enlarged, the second segment as large as or 

 larger than the first; flagellar segments small, brown. Head pale 

 with a broad dark brown mark on the vertex sending a small median 

 tongue backward onto the occiput. 



Pronotal scutum dark medially. Mesonotal preescutum light 

 brown with three dark brown stripes, the median one split by a 

 narrow vitta of the ground-color; scutum with the lobes dark brown. 

 Pleura pale yellow, striped with brown; a very short brown dorsal 

 stripe extending from the pronotum back to above the fore coxae; 

 second stripe beginning at the fore coxa extending caudad to the base 

 of the halter; ventral stripe broadest, including the sterna and the 

 bases of the middle and hind coxae; the pale stripe enclosed broad, 

 extending to the abdomen. Halteres pale. Legs with the coxae 

 pale; trochanter's darker; remainder of the legs broken. Wings 

 hyaline or nearly so, the veins brown; basal deflection of R i+b , r-m 

 and the basal deflection of Cih dark brown; a pale brownish gray 

 oval stigma. Venation (Plate XXVI, fig. 18) with Rs short, straight, 

 oblique, a little longer than the r-m cross-vein; basal deflection of 

 Cui at the fork of M. 



Male hypopygium (Plate XXIX, fig. 62) with the pleurites rather 

 prominent, cylindrical; ventral pleural appendage (y) elongate, 

 flattened, blade-like, the apex chitinized; a rounded lobe on the inner 

 ventral side just before the apex; at the base on the inner dorsal 

 side, a sharp, acute, chitinized point; middle appendage a slender, 

 slightly curved pale hook, directed inward, the apex slightly 

 chitinized; dorsal pleural appendage (d) a subtriangular lobe, the 

 caudal angle produced caudad as a short spine, heavily chitinized 

 at the apex, the inner angle prominent, produced slightly cephalad, 

 with numerous setigerous punctures. 



Allotype in the collection of Cornell University. 



The type is grayish, this color being produced by a pruinosity that 

 is not shown by the alcoholic allotype. 



The Pleuralis Group. 



Gonomyia (Leiponeura) sacandaga Alexander. 



Gonomyia sacandaga Alexander; Proceedings of The Academy of Natural 

 Sciences of Philadelphia, pp. 587, 588, PL 27, fig. 25 (wing) ; PL 26, fig. 21 

 (hypopygium) (1914). 



This species is still known only from the type station where it is 



common. 



