RHACHICERUS. 105 



facets, deeply notched and including a smooth space on each side 

 by the base of the antennae. Ocelli approximate. Proboscis not 

 prominent; palpi short. Antennae with 34 or 35 joints, tapering 

 slightly, much more than half the length of the body, deeply 

 serrated on each side; joints transverse, very short, cyathiform, 

 petiolated. Thorax elongate - quadrate ; abdomen pubescent, 

 8 -segmented, hardly tapering from base to tip, about twice as 

 long as thorax. Legs rather slender, moderately long ; hind 

 tibiae with very minute spurs ; ungues and onychia very small. 

 Wings narrow." 



Range. North and Central America, Cuba, India, Malay Archi- 

 pelago, and one species in Europe. 



Life-history unknown. 



Table of Species. 



Thorax orange nigricornis, sp. n., p. 105. 



Thorax black. 



Dorsum of first three abdominal segments 



mainly yellow bicolor, Brum, p. 105. 



Dorsum of abdomen all black, except a 



transverse yellow band on 2nd segment, unicincta, sp. n., p. 106. 



68. Rhachicerus bicolor, Brun. 



Rhachicerus bicolor, Brunetti, Rec. Ind. Mus. vii, p. 461 (1912). 



$ . Head with frons nearly one-third width of head, shining 

 black, bare ; three small yellow ocelli at vertex ; eyes blackish, 

 bare ; proboscis bright yellowy palpi of similar colour, very small ; 

 a whitish triangular spot on each side between the eyes and the 

 base of the antennae. Antennal 1st and 2nd joints black, 2nd 

 with a circlet of black and yellow bristles around its tip ; flagellar 

 1st joint much wider than the rest, which are blackish brown, the 

 comb-like prolongations on the underside bright yellow. (The 

 antennae being incomplete, the exact number of joints cannot be 

 giveu.) Thorax and scutellum wholly shining black, practically 

 bare ; humeri conspicuous, bright yellow. Abdomen black, dorsum 

 of first three segments mainly yellow, the borders being black, the 

 4th segment being more or less yellow in the centre ; venter 

 principally yellow on the first three segments, remainder blackish. 

 Legs bright yellow, hind coxae black. Wings with venation as in 

 Xyhmyia, grey, with a hardly perceptible darkening from the 

 costa partly across the wing, and again towards the tip; halteres 

 bright yellow. 



Length, 8| mm. 



Described from one $ in good condition in my collection from 

 Kandy, v. 1909 (E. E. Green). 



69. Rhachicerus nigricornis, sp. nov. (PI. II, fig. 1.) 



S . Head black ; frons at vertex less than one-fourth width of 

 head, widening to one-third at level of antennae, with some 

 whitish dust around base of antennae ; scape of latter yellow, with 

 short black bristles, flagellum black for 23 joints, with the comb- 



