ART. 16. NORTH AMERICAN SCELLUS GREENE. 1 1 



below before the middle and two or three smaller ones. Allied to 

 ■fUifems Loew, but that species has niunerous shorter spines on front 

 basitarsi and dense ciliate hairs behind on the middle tibiae. 



" Length, almost 5 mm., wing 6.5 mm. 



" Male. — Face narrow, widened below, ocher-yellow ; front yellov/ 

 with some ocher pollen; the ground color bronze green; occiput 

 yellow, with cupreous reflections. Palpi yellow, proboscis black. 

 Antennae black, shining; third joint elongate oval, subpointed above, 

 a little swollen at the origin of the arista; not shining, with short 

 whitish hair. Basal portion rather thick; last section slender, 

 curved about its middle. 



" Thorax cupreous bronzed, rather thickly grayish pollinose, but 

 not completely obscuring the ground color, dorsum with two nar- 

 rowly separated median brownish stripes, abbreviated behind, and 

 an obscure similarly colored stripe above the wings. Each of the few 

 hairs arises from a black spot. Pleura much less densely pollinose. 

 Scutellum moderately pollinose. 



" Legs black, femora bronzed, tibiae more greenish. Fore femora 

 thick basally, gradually tapering. Anterior tibiae with the sub- 

 basal spur black, its upper surface yellow pollinose, and with pale 

 yellowish hairs; just below the origin of the spur, on the outer side 

 a long black spine, with a shorter one above it; apex of tibiae pro- 

 duced as a rather broad, blunt lobe, which is of about the same 

 length as the last tarsal joint; the lobe behind with thr'ee or four 

 black bristles, its anterior and apical margin with S*"'fringe of short, 

 black hairs ; immediately above the lobe in front the tibia is fringed 

 with yellow hairs, dense and longer apically; beneath toward the 

 front is a row of black bristles, longer apically, behind, on the swollen 

 subbasal fourth with much longer bristles. Front basitarsi postero- 

 ventrally, just before the middle, with a long bristle and two or 

 three short ones before it on posterior surface. Middle femora 

 strongly arcuate, the apical two-thirds swollen, beneath, on the hind 

 surface with a single row of black bristles, but these are mixed with 

 the long, bristly hairs on the upper half, and not distinguishable; 

 anterodorsally is a row of five or six bristles on the apical third. 

 Middle tibiae also moderately arcuate and swollen on basal portion, 

 the posterior surface flattened; bearing long, not very abundant 

 hairs which appear slightly tufted, and especially marked on the 

 swollen area; above the middle on the outer side with tv^o bristles 

 and a slightly stouter one just before the apex; apex swollen and 

 polished, more extensively so on the posterior side; just above this 

 area on the inner side a stout, apically curved bristle. Middle basi- 

 tarsi on either side below with a row of long spines. Hind femora 

 laterally compressed, bearing dorsally two subapical bristles and a 

 posterior one just before the apical dorsal one. Hind tibiae a little 



