ALDRICH : NKW GK.NERA AND SPECIES OK PSILOPIN^.. 4^ 



before the tip; on each side of the first segment a bunch of long 

 yellow hairs; hypopygium black, closely folded up to the venter, the 

 small apical organs yellow. Coxae green; the fore and middle ones 

 with long white hairs on the front side; trochanters yellow; femora 

 green, rather broadly yellow at the tips, with white hairs, longer 

 below, especially on the middle and hind femora; fore and middle 

 tibiae yellow, the hind ones brownish-yellow; all the tarsi gradually 

 infuscated toward the tip; the fore and middle tarsi are considerably,, 

 the hind ones scarcely, longer than their tibiae. Wings hyaline, the 

 venation as described. 



Female. Pollen of face white, lateral bunches of hair on the front 

 brownish-black, the central bunch very short, whitish; hairs of the 

 second antennal joint rather short, brown; abdomen with shorter 

 hairs, lacking the white ones on the first segment: femora and hind 

 tibiae wholly yellow, the former with short hair. 



Length, 4 mm.; of wing, 3.5 mm. 



Two males and two females, Westville, N. J., July 5 and 20 (C. W. 

 Johnson). 



Aptorthus borealis n. sp. 



Female. Differs from the female of the preceding in having yellow 

 fore coxae, brownish at base; on each side of the front near the eye 

 are only a few small black bristles. 



One female, Ramsey Co., Minn. (Lugger). 



Aptorthus nigripes n. sp. 



Female. Face white-dusted; palpi and proboscis brown; antennae 

 black, second joint with black or dark brown hairs; front shining 

 green, the two bristles of the ocellar tubercle black, behind the tubercle 

 a cluster of small, white ones; on each side next the eye are a few 

 white bristles and two black ones farther forward. Cilia of inferior 

 orbit white. Thoracic dorsum shining blue-green; pleurae blackish- 

 green, with white dust; tegulae white with a narrow black edge and 

 long white cilia; halteres yellow, abdomen blue-green, shining, with 

 black hairs, which are mixetl with a few paler ones at the sides near 

 the base. Coxae blackish-green, with conspicuous white hairs. 

 Femora of the same color, with black hairs except on the lower edge, 

 where the hairs are pale and rather short; knees yellow; fore tibiae 

 brownish-yellow, the middle and hind ones, with their tarsi, brown. 

 Fore tarsi brownish-yellow at base, darker toward the tip. Wings, 

 hyaline, venation as above described for the genus. 



Length, 4 mm.; of wing, 3.5 mm. 



One female, (California, .\ug. 5 (Coquillett). 



