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UNITED STATES NATIONAL MUSEUM BULLETIN 2 63 



Thorax 1.4 limes us long as wido, sliiilitly limocr than 

 higli, black, distiiu'tly dusted with dense yellowisli or 

 brownish-grey tomciitiiiii, coxered with yellowish pu- 

 bescence. Mesonotuni (pi. 32, fiij. 6) slis^htly longer 

 than wide, with three narrow indistnict brown longi- 

 tudinal streaks not attaining posterior margin, the 

 median streak almost always very fine and very often 

 obsolete; humeral and notopleural calli almost always 

 more yellowisli tomentose and bare, but former with 

 yellowish erect bristly liairs; scutellum three-fifths as 

 long as wide, witliout distinct lateral carinae, disk 

 without pubescence, posterior margin with A-ellowish 

 setae, of wliich the two apical ones are conspicuous. 



Pleura (|)1. 32, fig. 5) less tomentose and pubescent 

 tlian notum, the tomentum whitish grey, prothorax 

 with short yellowish bristly hairs; superior ])order of 

 mesopleuron with many short yellowisli bristly hairs 

 dii'ected u|)ward, posterior border witli some yellowish 

 bi-istles directed posteriorly, one or two of which are 

 conspicuously long; pteroplem-on with two or three 

 whitish bristly hairs below yellowish i)tei'o])leural 

 bristle, wliicli is directed jiosteriorly; stei'uopleuron 

 quite bare, but ventral margin with many ratlier long 

 whitish hairs; mesophragma and postnotum veiy 

 slightly whitish tomentose. All bristles 1)lack, exce])t 

 sca]iular and pteropleurals yellowish white. Humerals 

 as long as ])resutural or anterior notopleurals, posterior 

 noto]ileural very short; dorsocentrals very rarely two 

 pairs; if so, one pah- placed ahead of sutures, remaining 

 pair in normal position, normal pair nearly parallel 

 and distinctly ahead of level of anterior supra-alars 

 but nearer to it than to sutvu'e; prescutellars slightly 

 ahead of line connecting inner posterior supra-alars, 

 shorter than the latter, as long as dorsocentrals; outer 

 scajjulars conspicuous, inners very weak; scutellars 

 one basal pair, the longest of all tlioracic bristles, 

 median i)air of wliitish margiiuil setae rather conspicuous 

 and nnvy be mistaken for apical bristles. 



Abdomen (pi. 32, fig. 7) distinctly longer tlian thorax, 

 black, entirely obscured by yellowish or brownish-grey 

 tomentum, covered with rather long sparse yellowish 

 ])ubescence, one pan- of large brown rather ill-defined 

 patches on each of the terga except basal one, the latter 

 uniformly blackish; fourth tergum witli four pairs of 

 long j-ellowish marginal bristles, the outer pair some- 

 times black; fifth tergum with one j)air of long black 

 marginal bristles; genitalia com[)aratively small, 

 shining black or brown. 



Wing (pi. 32, fig. 1) very slightly longer than the 

 body, 2.8 tunes as long as wide, apex rather narrowly 

 rounded, with one or two short costal s])ines; subcosta 

 obliquely directed toward costa apically; R2+3 very 



slightly sinuate; R4+5 not bristled, straight, jjarallel 

 with m; r-in ])er]5endicular, distinctly beyond middle 

 of iMo and end of R,; m-cu straight or very slightly 

 wavy, convergent with r-m; ])terostignui nearly half 

 as long as second costal cell, pouited; anal cell nearly 

 as long as basal cell, with a very short pointed lower 

 angle. Basal one-third of wing hyaline, renuiiiuler 

 brownisli with many hyaline spots. Pterostigma ])lack- 

 isli, extreme posterior base hyaline; second costal cell 

 hyaline witli a brown median spot along costa, immedi- 

 ately beliind this spot two ill-defined Ijrownish spots, 

 the anterior at base of R2+3, the posterior at inferior 

 ajiical angle. Hyaline spots in brownish ])ortion as 

 follows: R, witli a large spot just beyond [iterostigma, 

 two smaller closely placed spots beyond middle; R3 

 with six spots, the apical just beyond end of R2+3, 

 almost always the largest and connected with small 

 lower one, tJie second just below the two distal spots 

 of Ri, the following two just below proximal large 

 spot in R,, the remaining spot occupying entire basal 

 portion; R-, with fixe spots, the basal very large, filling 

 basal one-fourtli of cell, the following spot at about 

 middle along m, small and round, the two subai)ical 

 below lower ajjical spot of R3 transversely situated, 

 and the apical spot just at inferior corner of cell semi- 

 circular, often in addition two very snuiU faint trans- 

 verse spots; R with two faint spots; iMo with five 

 spots, the proximal very large, occupying basal one- 

 third, the next two below the apical spot of R l)andlike, 

 connected to each other, and the distal two also trans- 

 A^ersely united to each other aiul closer to ])receding 

 spots than to m-cu; 2M2 witli three round equidistant 

 spots along wing margin and a similar spot near anterior 

 basal corner of cell; Cu with four spots, the basal very 

 large, occui)yhig basal two-fifths, the median two 

 transverse, always connected to each other, the re- 

 maining siK>t near apex, in addition one small very 

 faint sj)ot at end of anal veui. Halteres light reddish 

 brown; squamulae greyish. 



Legs light redtlish yellow to light reddish brown, the 

 basal two-tiiirds of femora blackish, but often front 

 and middle pairs pale mlored tliroughout entii'e length 

 of ventral surface, lilack i)ubescent. Foreleg (pi. 32, 

 fig. 11) conspicuously shorter than others as usual: 

 femur very slightly longer tlian tibia, externoventral 

 marghi with one row of four or five black long bristly 

 hairs, dorsal surface with five or sLx bristly hairs, the 

 basal three or four almost always yellowish white; 

 tibia very slightly shorter than tarsus, externoventral 

 a|)ex almost always with two very short whitish bristles; 

 first tarsal segment nearly half as long as tibia, slightly 

 longer than the four following segments together, 

 brushlike bristles on internoventral surface rather fine. 



