F. R. COLE 55 



marked, except that spots are quadrate and very narrowly sep- 

 arated at posterior margin. Fourth segment largely yellow, with 

 dorsal triangle and small triangles at anterior angles, black; 

 venter black; with narrow white posterior margins on all seg- 

 ments. Legs a very light yellow, last tarsal joint and claws black, 

 halteres yellow. Length, 4.5 mm. This specimen is a female. 



Specimen collected by S. W. Bromley, at Southbridge, Massa- 

 chusetts, has dark yellow markings, the two widely separated 

 spots on second segment are quadrate, those on third triangular 

 and narrowly connected, and those on the fourth quadrate and 

 also narrowly connected at posterior margin. The wings and 

 squamae are slightly darker hyaline than the Maine specimen. 

 The abdomen is contracted. The rims of the squamae are black; 

 venation typical. Humeral callosities yellow, the prescutellar 

 callosities mostly blackish. Legs pale brown. Veins of wing, 

 distinct and black. This specimen is a female. Length, 5.5 

 mm. A very similar specimen is from Colebrook, Connecticut, 

 August 14, 1910 (A. L. Melander coll.). 



The above mentioned specimens from Franconia, New Hamp- 

 shire, Williams, Arizona, and Medicine Hat are all males and are 

 much alike. It may be that they do not belong with the females 

 described under this species. The abdomen is yellow and the 

 black abdominal markings small (see fig. 27a). The squamae are 

 whitish with whitish rims. The praescutellar callosities are 

 darkened in the specimens from Arizona. The legs are whitish 

 yellow, the terminal half of last tarsal joint black. 

 Acrocera bulla var. melanderi new variety 



9 . Head black. Thorax and scutellum black, shining. Pleura black. 

 Thorax, pleura and scutellum with rather short grayish pile. Four corners of 

 thorax (callosities) whitish. 



Abdomen black, shining, a narrow yellow rim at extreme base. Markings 

 much resemble bulla. Second segment with two roughly triangular orange 

 yellow spots. Third segment with two similar spots, but they are larger and 

 connected by the narrow yellow posterior border of the segment. End of 

 fourth segment 3'ellow. Genitalia black above at base. Fifth segment with 

 a narrow yellow posterior border. Venter black. 



Legs yellowish, brownish on femora and tips of tibiae. Most of last tarsal 

 joint black. Venation as in bulla. Veins brown. Last section of costa black. 

 Auxiliary vein black. Abdomen is distorted and wings slightly mutilated. 

 Length, 5 mm. 



TRANS. AM. ENT. SOC, XLV. 



