1913] Agromyza and Cerodontha. 281 



is brown; outer cross vein more than its own length from inner cross 

 vein, first and second sections of fourth vein equal; first portion of fifth 

 two-thirds as long as last portion. Halteres yellow. Length, 1.5 mm. 



Type: Cat. No. 15560, U. S. N. M. 



Much as I dislike the idea of describing a new species 

 from a single specimen, I believe that in this case I am justified 

 in doing so, as the specimen is in good condition and presents 

 some good characters for its separation from longispinosa 

 and its allies. (Compare arcticum Lundbeck) 



7. Agromyza flavonigra Coquillett. 

 Plate XXX, Fig. 27. 



vSyn: Agromym flavonigra Coquillett, Jour. N. Y. Ent. Soc, Vol. 10, 1902, p. 189. 



Female: Head yellow, ocellar region and back of head brownish or 

 blackish; frons distinctly, but not greatly, wider than one-third the head 

 width; almost parallel-sided; the orbital bristles strong, black; antennee 

 rather small, yellow, third joint rounded in front, arista brown, yellow 

 at base, almost bare, and falling just short of reaching to vertex; base 

 distinctly swollen, elongate; cheeks broad, one-third higher pos- 

 teriorly than anteriorly, and at former place one-half as high as eye- 

 height; marginal bristles of moderate length, vibrissa not strong but 

 distinctly longer than the other marginal bristles; proboscis and palpi 

 yellow; palpi linear, with numerous short, black bristles. Mesonotum 

 marked much as in melampyga, but the posterior quadrate excision in 

 center has two linear, yellow, anterior prolongations which divide the 

 black portion more or less disticntly into three vittse; the posterior, 

 longitudinal, yellow, dentiform incision of the outer lobe is also pro- 

 longed, and separates the outer portion of the posterior half of the 

 black mark, so that it forms a separate black stripe giving the dorsum 

 the appearance of having five vittae. Four pairs of dorso-central 

 bristles present, the anterior two pairs somewhat reduced in size. In 

 other respects the thorax is much as in melampyga, but the fringe of the 

 squamae is pale and there is a lateral black spot at base on each side of 

 scutellum. Abdomen yellow; first to fourth segments with a dorsal, 

 brown, central spot, fifth with a pair of close placed spots on center of 

 disk, sixth with a pair at near base which are wider placed than those on 

 fourth, and another larger pair more widely placed at about middle; 

 sixth segment about four times as long as fifth; base of ovipositor 

 glossy black, conical, as long as sixth segment; all segments with 

 numerous black hairs, those on apices of last two segments bristle- 

 like. Legs yellow, brown on base of fore coxae, bases and apices 

 of all femora, as well as the entire tibiae and tarsi of all legs. Wings 

 much as in melampyga, but the inner cross vein is rather before 

 the end of first vein, the second portion of fourth vein is shorter than 

 first, the outer cross vein rather oblique, and the first section of fifth is 

 shorter than in melampyga, being only two-thirds as long as last section. 



Length, 3 mm. 



Locality — Beulah, New Mexico, (T. D. Cockerell). Re- 

 described from type specimens. Food-plant unknown. 



