370 PROCEEDINGS OF THE NATIONAL MUSEUM vol. iog 



Pile: Yellowish brown; on eyes, occiput, mcsonotum, mesopleura, 

 scutolhini. and lergite I about as long as antonnal segment I, that 

 on abdomen much sliortor, concolorous with ground color, about 

 oni>-half as long as rest of pile; 3'ellowish wliite on legs, propleura, 

 upper sternopleura, meropleura, and squama. 



IIeao: With ocellar tubercle elevated; antemial tubercle large 

 (fig. \,b): proboscis concealed behind cone-shaped tubercle; anleiniae 

 much longer than head height, segment I of each anteima fused on basal 

 half, sinning, apilose, produced above over segment II, about as long 

 as eye width, segmc^nt II about half as long as I, covered with short, 

 sparse hairs, segment III longer than head lieight, concave in outer 

 median area, concave region with few scattered hairs. 



Tnoiux: Well arched in front; scutellum little wider than long; 

 sciuama greatly expanded behind near thorax, opaque, curved sharply 

 along distal inner margin; femora progressively longer from first to 

 third, each longer and in same proportion to tibiae I-III; each tibia 

 with two (inner and outer) subequal spurs, each spur nearh^ as long 

 as corresponding tarsal segmxent II; metatarsus about as in figure 4, .7, 

 but a little longer, leiigth of segments II-IV equals distitarsus, 

 basitai-sus not as expanded distally; wing with five posterior cells, 

 fourth not bounded basally by second basal cell,vein R2+3 incomplete, 

 not reaching wing margin, vein R4 swinging upward near apex causing 

 narrowed subnuirginal region, anal cell narrow, about as long as 

 second basal cell, basal cells nearly equal lengtli, m crossvein about 

 three times r-m crossvein. 



Aj!D0.mi;n: Rather compressed dorsoventrally, flattened beneath, 

 slightly convex above, tergite I cleft medially, well raised along pos- 

 terioi- marghi; stigmata free in intersegmental membrane of seg- 

 ments II-IV; genitalia not examined, broken off inside specimen. 



HoLOTYPi:: Islale; Cantarera, near Sao Paulo, Brazil (Wettstein 

 Brazil Expedition, 1891). Tlie type will be deposited in the Vienna 

 Naturhistorische Museum., Austria. 



Re.aiakks: The characteristic incomplete vein R243 of capitella 

 shows a relationship to ecuodorensis, but Avhetlier this is a factor of 

 relative or convergent evolution is not determined. Such other 

 characteristics as two tibial spurs and the larger eyes causing a 

 different sliaped head capsule are distinctions which suggest a more 

 distant relationship. This species is probably closer to lomaia, as 

 discussed under the latter. Also, the character of the two equal-length 

 basal cells in capitella is unique for the genus, and it therefore secm.s 

 that this species has no know^n close relative. 



The name capitella jcfers to the minute^ head, which is also a charac- 

 ter of Rialea. 



