1913] Agromyza and Cerodontha. 299 



setulae; lateral margins and humeri brown; pleurse glossy brown-black; 

 upper margin and central, vertical, suture narrowly, and a patch 

 below wing base yellow; scutellum distinctly broader than long, con- 

 colorous with disk of mesonotum; postnotum concolorous with pleurae; 

 squamse yellow, margin and fringe brown. Abdomen glossy brown, 

 or black-bro^¥n, posterior margin of last segment sometimes narrowly 

 yellowish; last abdominal segment almost as long as the three pre- 

 ceding seginents, ovipositor elongate, glossy black; male hypopygium 

 knob-Uke, of moderate size, about one-fourth as long as preceding 

 abdominal segment ; surface hairs most numerous on the sides of second 

 segment, and longest on apical segments. Legs yellow; basal half 

 of each femur brown-black, apices of tibiae and all tarsi more or less 

 browned; posterior mid tibial bristles absent. Wings grayish; first 

 costal division one-third as long as second, subcostal vein indistinct, 

 but complete, inner cross vein at just below end of first vein, outer 

 cross vein -at distinctly more than its own length from inner and at 

 wing middle; first and second sections of fourth vein subequal; penu- 

 timate section of fifth vein slightly shorter than ultimate; outer half 

 of last sections of veins 3-4 almost parallel. Halteres clear yellow. 

 Length, 1.5 mm. 



Originally described from District of Columbia (Osten 

 Sacken) . 



Represented in collection by three specimens, two females 

 and one male, from Beverly, Massachusetts (Burgess). These 

 specimens bear the dates May 28, 1868; August 28, 1869; and 

 May 24, 1874, respectively. 



Food-plant unknown. 



25. Agromyza canadensis, new species. 

 Plate XXX, Fig. 19. 

 Female: Frons opaque, brown, sides subparallel, in breadth one- 

 third the width of head and distinctly longer than broad, orbits shghtly 

 differentiated, subshining; orbital bristles five in number, situated near 

 to inner margin of orbits, decreasing in size from back to front; no hairs 

 on orbits in addition to bristles; ocellar region shining, the anterior 

 ocellus separated more widely from posterior ocelli than posterior 

 ocelli from each other; antennse yellowish-red, third joint brown; 

 second joint with strong dorsal bristle, and weaker apical hairs; third 

 joint rather elongate, one-third longer than broad, rounded at tip; 

 arista brown, yellow, and with an elongate swelling at base, pubescence 

 very weak, distinctly shorter than basal diameter of arista, length of 

 arista as long as from its base to between upper two orbital bristles; 

 face in profile perpendicular, yellow, with whitish dusting and distinct 

 keel, a blackish line on each side of keel, cheeks linear, only slightly 

 higher at posterior margin than anteriorly, brown, paler on margins; 

 marginal bristles upturned, of moderate strength; vibrissa strong; 

 the weak bristles are continued upward beyond the level of vibrissa; 

 proboscis yellow; palpi brown, slightly spatulate, with distinct bristles. 



