1913] Agromyza and Cerodontha. 301 



brownish yellow; four pairs of dorso-centrals present; discal setulise 

 rather strong; the pair of bristles between the posterior pair of dorso- 

 centrals distinct, but not large; pleurag glossy black, narrowly lemon 

 yellow along upper and medium vertical suture, and broadly below 

 wing base; squamae almost white, fringe concolorous; scutellum and 

 postnotum gray black. Abdomen glossy black, or black-brown, 

 posterior margins of segments generally narrowly yellow, sometimes 

 the base of abdomen yellow laterally; hypopygium of male small; 

 ovipositor of female glossy black on basal portion. Legs black, or 

 black-brown, knees distinctly pale yellow; mid tibia without distinct 

 bristles on posterior surface, except in one specimen. Wings clear, 

 basal part of thick veins pale yellow; subcostal vein indistinct, but 

 complete; second costal division about 23/^ times as long as first; inner 

 cross vein at just before end of first vein, and at about middle of discal 

 cell; last cell section of fifth vein subequal with penultimate section; 

 veins 3-4 slightly divergent on their last sections. Halteres yellow. 

 Length 1.5-2.5 mm. 



Localities of specimens examined: Algonquin, Illinois, 

 (collection Coquillett); Franconia, New Hampshire, (Mrs. 

 A. T. Slosson) ; Biscayne Bay, Florida, (Mrs. A. T. Slosson) ; 

 Rosslyn, Virginia, October, 1903, (E. S. G. Titus) ; Beverly, 

 Massachusetts, June 1, 1868, (Burgess); another same collector 

 and locality, June 2, 1876; Worcester, Mass., "Gall on Iris" 

 (no collector's name) ; and South Fork, British Columbia, 

 (R. P. Currie). There are specimens in C. W. Johnson's 

 collection from Chester and Framingham, Massachusetts. 



This species has been recorded by Thomson,* as feeding 

 galls on blue Iris, and although there is no collector's name 

 on the Worcester specimen mentioned above, it is very proba- 

 bly belongs to the lot reared by him, as Coquillett identified 

 specimens. 



This is a very variable species in color, and structure of 

 the antennae, and one might be easily led into considering 

 some of the forms as distinct species. I am, however, con- 

 vinced from my acquaintance with the species in Britain, that 

 there is but one species, though it probably feeds upon different 

 food plants, as I have met with it in situations where it could 

 not have fed upon Iris. 



*Psyche, Vol. XIV, 1907, p. 74. 



