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UNITED STATES NATIONAL MUSEUM BULLETIN 224 



prominent below ; its posterior margin is largely plane. 

 Pile of occiput rather fine and long, bristly on the 

 upper half, longer and more curled below; the more 

 medial elements laterally become a little stronger and 

 more bristlelike; the dorsal elements are a little 

 stronger but are quite slender in the type of genus. 

 Proboscis thrust forward or slightly upward; at the 

 apex it is curved upward into a quite sharp tip. The 

 apical third bears a little short, stiff, scanty pile above 

 and below. Dorsal ridge absent ; ventral groove pres- 

 ent, the base is very strongly swollen, the whole struc- 

 ture tapered both laterally and dorsally and rather 

 subquadrate in section; the base has abundant, long, 

 fine pile. First segment of palpus small, short, and ex- 

 cavated. The second segment is long, moderately wide, 

 flared, and excavated, with a few bristles ventrolater- 

 ally at the apex. 



Head, anterior aspect : The face below the antenna is 

 not quite a third the head width and only slightly diver- 

 gent below. Subepistomal area small, concealed by the 

 palpus and the proboscis and only slightly oblique. The 

 face is pubescent, sometimes bare in the center ; it bears 

 abundant, long, fine pile laterally below the antenna. 

 Above the epistoma but widely over the central knob 

 are numerous, long, stout bristles that thrust outward 

 and reach beyond the tip of the proboscis. Antenna at- 

 tached at the upper third, the first segment nearly 

 twice as long as the second. The third segment is l 1 /^ 

 times as long as the first two and regularly oval at the 

 middle; it is less than twice as wide as the second seg- 

 ment and regularly tapered to the base and apex. The 

 apex bears a moderately large, dorsomedial, circular 

 opening carrying a concealed spine. The first segment 

 has 5 or 6 long, stiff hairs dorsally and considerably 

 more hairs and bristles laterally and ventrally. Some- 

 times there may be 1 extremely stout, long bristle nearly 

 as long as the third segment. Second segment with 

 several stout bristles ventrally and dorsally and 1 very 

 long, attenuate, basally stout bristle, considerably 

 longer than the third segment. The front is extremely 

 short and bare with 3 stout bristles and some long, stiff 

 pile. Close beside the eye margin is considerable pile 

 on the sloping sides of the deeply excavated vertex. 

 Ocellarium moderately large, obtusely rounded and 

 bearing 2 pairs of long, divergent bristles; the anterior 

 element is quite stout, the posterior element moderately 

 stout. Eye facets strongly enlarged centrally. 



Thorax : The thorax is pollinose or appressed micro- 

 pubescent with bands, spots, or stripes. Pile of meso- 

 notum moderately abundant but everywhere bristly. 

 Acrostical bristles are present in 1 or 2 rows; dorso- 

 central bristles begin to be differentiated before the 

 suture and become long and slender posteriori} 7 . Hu- 

 merus with numerous, slender bristles. Posthumeral 

 and notopleural area with 10 to 12 long, slender, bristly 

 hairs and 1 very stout, long bristle. Very long, stout 

 bristles are present on the remainder of the mesonotum 

 as follows: 3 supraalar, 6 to 8 postalar, 4 or 5 pairs on 

 the scutellar margin. The scutellum is thick, pu- 

 bescent basally, fused to the base in the middle with 



strongly impressed rim and abundant, moderately long, 

 more or less erect, bristly pile. Propleuron with nu- 

 merous, long, stiff hairs and weak bristles; the pro- 

 notum has an exceptionally copious fringe of slender 

 bristles in several rows. All the dorsal and postpro- 

 pleural bristles are quite slender. The upper and ante- 

 rior sternopleuron, pteropleuron, hypopleuron, upper, 

 and posterior mesopleuron bear abundant pile; poste- 

 rior upper mesopleuron has a large, dense tuft of many, 

 slender bristles and at least 1 quite stout bristle. 

 Metapleuron with a wide band of numerous, very long, 

 apically bent, moderately stiff bristles. Metanotal 

 slopes densely, bristly pilose. Lateral and ventral 

 metasternum pilose; postmetacoxal region membranous 

 but posteriorly reduced to a third the area width by 

 encroaching chitin; tegula with bristles; squama with 

 a long fringe in several rows. 



Legs : All the femora are stout, the hind pair a little 

 swollen from the base, plane below, arched above. 

 The pile of the legs tends to be appressed dorsally on 

 the femora, medially or posteriorly on the tibia but 

 long, erect and bristly elsewhere. Hind femur with 

 only a sparse fringe of the short, erect pile which be- 

 comes more abundant on its tibia; a brush of setae is 

 restricted to the extreme apex. The type of genus has 

 bristles which consist of 1 stout lateral at the outer 

 fifth of the hind femur, 1 medially and 1 above it dor- 

 somedially. On the tibia are 4 slender, long bristles 

 dorsally, 2 or 3 dorsomedially. Middle femur with a 

 close-set pair of 2 stout bristles posterodorsally near 

 the apex, none anteriorly. This tibia is characteristic 

 for its extremely long, slender, bristly hairs, or weak 

 bristles; there are 10 to 12 pairs of anteroventral bris- 

 tles, 7 posterior, 8 or more posteroventral, and 2 or 3 

 rows of a like number of ventral bristles, besides addi- 

 tional, short, erect pile anteroventrally and subap- 

 pressed pile posteriorly. Anterior femur and tibia 

 quite similar to the middle pair, with bristles lacking 

 on the femur and the anterior elements of the tibia 

 either lacking or greatly reduced; but all the posterior 

 and ventral elements are similar and equally promi- 

 nent. Basitarsus a little more than twice as long as 

 wide; next three segments dilated apically and wider 

 than long. All tarsi end in stout, sharp claws, chiefly 

 bent at the apex, long, wide pulvilli and stout, blade- 

 like empodium. 



Wings: The wings are slender and a little longer 

 than the abdomen. Marginal cell closed with a long 

 stalk; the anterior branch of the third vein ends well 

 above the apex; the posterior branch far behind. The 

 first posterior cell is greatly narrowed throughout its 

 length, closed in the margin; fourth posterior cell 

 closed and stalked. Lower end vein of the discal cell 

 pulled far backward and parallel with the anterior 

 margin of the cell. Anal cell closed and stalked ; alula 

 large, ambient vein complete. 



Abdomen: The abdomen is robust, as wide as the 

 mesonotum and rather flattened. Pile of abdomen 

 dense, fine, short, subappressed, becoming longer but 

 scanty along the margins. First tergite with 3 or 



