1913] Agromyza and Cerodontha. 297 



sometimes brownish, pleurse brown-black, subshining; upper margin, 

 central vertical suture, and below base of wing narrowly yellow; scu- 

 tellum concolorous with mesonotum, four bristled; postnotum brown- 

 black, shining. Abdomen shining brownish or blackish; ovipositor 

 glossy black, base slightly longer than last abdominal segment, covered 

 with numerous short hairs. Legs brownish; fore coxa, apices of all 

 femora broadly, and bases of tibiae yellow ; the basal two pairs of former 

 are generally almost black; posterior bristles absent from mid tibiae. 

 Wings elongate, clear or slightly grayish; first costal division one-third 

 as long as second; inner cross vein at just below end of first vein or very 

 slightly beyond it; outer cross vein distinctly shorter than section of 

 fourth vein anterior to it, first and second sections of fourth vein sub- 

 equal; last two sections of fifth vein subequal. Halteres pale yellow. 

 Length, 2.5 to 3 mm. 



Originally described from District of Columbia (Osten 

 Sacken) . 



Represented in collection by two specimens from Mount 

 Washington and Franconia, New Hampshire, (Mrs. A. T. 

 Slosson, collection Coquillett) ; and two from Algonquin, 111., 

 (collection Coquillett). Three of the specimens were stand- 

 ing as A. xanthocephala Zetterstedt, in collection. This iden- 

 tification ' may have been given out by Coquillett, though I 

 cannot find any published record of the name. Zetterstedt's 

 species differs from Loew's in having the legs entirely black, 

 Longipennis comes very close capitata Zetterstedt as under- 

 stood in Britain, but I have no specimens for comparison, and 

 as Kertesz gives capitata as a synonym of geniculata, which I 

 have from Holland, and find distinct, I consider it advisable 

 to continue the use of Loew's name, meantime. 



Food-plant unknown. 



23. Agromyza coloradensis, new species. 

 Male and Female: Frons opaque, ochreous yellow, about one-third 

 longer than broad, sides almost parallel; orbits at lunule not one-half as 

 wide as center stripe at same part; five pairs of orbital bristles present, 

 the one nearest antennae weakest; these bristles occupy middle of orbit 

 and laterally beyond them is an irregular row of short hairs which 

 extends from base of antennae to fifth orbital bristle; vsides of orbits and 

 back of head blackened; ocellar region shining black; antennae black; 

 basal joint and apex of second on inner surface yellow; second joint with 

 numerous short hairs on dorsal and ventral surfaces, the dorsal bristle 

 distinct; third joint of moderate size, slightty longer than high, regularly 

 rounded on the upper margin or apex obtusely angled; arista black, 

 sHghtly thickened at base, the pubescence thick but very short, arista 

 in length reaching to front ocellus; face and cheeks pale yellow, the 

 former concave and very slightly keeled in center; cheeks higher pos- 



