506 



men before me which I consider referable to this species has the thorax 

 glossy yellow, the vitta:? black, almost confluent, the scutellum, postno- 

 tum, and greater portion of pleurae shining black, the abdomen opaque 

 black, wdth the base of first segment broadly and the apices of remain- 

 ing segments narrowly yellow. The legs, especially the fore tibiae and 

 mid and hind tarsi, are noticeably paler than in flavihasis. The fore 

 tarsi are missing in my specimen, but no mention is made by previous 

 authors of the presence of long hairs, which distinguish flavibasis. 



Length, 1.75-2.25 mm. 



Illinois localities: Illinois River near Havana, September 13, 

 1895; Chicago (Johannsen). 



Originally described from Europe. Recorded for New Jersey by 

 Johnson. 



Early stages undescribed. 



5. Cricotopus slosson.^, n. sp. 



Female. — Black. Head yellowish brown ; antennae yellow, flagel- 

 lum pale brown ; palpi brown. Mesonotum glossy black, anterior an- 

 gles and pronotum yellow, pleurae glossy black, yellowish on upper 

 margin; scutellum opaque, velvety black; postnotum opacjue black. 

 Basal two segments of abdomen lemon-yellow, remaining segments 

 velvety black ; genitalia pale yellow. Legs fulvous ; apical joint of mid 

 and hind tarsi brownish, other parts blackened as follows : basal 

 portions of hind coxae, all femora from before middle, bases of all tibiae 

 and their apices broadly, and the entire basal joint of fore tarsi and 

 from middle of third to apex of fifth joint. Wings clear, veins brown- 

 ish. Halteres whitish yellow. 



Frons half the width of head ; antennae shorter than palpi and 

 rather slender, the palpi robust. Pronotum rather broad, carried al- 

 most to upper margin of mesonotum, central incision weak. Basal 

 joint of fore tarsi more than two thirds the length of fore tibiae (45 : 

 65) ; second joint almost half as long as basal. Cross vein upright, 

 rather thick, distinctly before middle of wing; third vein distinctly 

 thicker than costal, ending beyond beginning of apical curve, but far- 

 ther from apex than fourth; cubitus forking slightly beyond cross 

 vein. 



Length, 3-3.5 mm. 



Type locality, Algonquin, 111., June 4, 1894 (W. A. Nason). Para- 

 type from Mt. Washington, N. H. (Mrs. A. T. Slosson). 



Named in honor of Mrs. A. T. Slosson. 



C. varipcs Coquillett agrees fairly well with the above description, 

 but the fore tarsi in the female are of a uniform brown color. The 



