SPONGILLA-FLIES — PARFIN AND GURNEY 487 



spots; Rs usually forking into R2-f-3 and R4+5 below pterostigma 

 slightly distad of or at about level of point of coalescence of Sc and 

 Rl; MA with terminal fork below pterostigma; MPl-f-2 usually 

 forking proximal to or at about level of point of coalescence of Sc 

 and Rl, and forking into uneven fork, with first fork closer to stem 

 and with first branch of first fork at an angle; Cul with four to six 

 branches to margin (five most common); about 12 or 13 costal cross- 

 veins before pterostigma; three radial cross-veins, 1st r usually basad 

 of midpoint of free stem of Rs, 2d r to Rs, 3d r below pterostigma 

 to Rs, R2-f 3 or to fork; 2d r-m usually slightly distad of 3d r (oc- 

 casionally directly under) and Rs fork, the outer gradates (five) 

 being irregular at this point; 2d m between MA and MPl+2 usually 

 slightly distad of, occasionally directly under, 1st r-m; 3d m long, 

 obliquely directed basad so as to make cell between 2d and 3d m as an 

 inverted trapezoid; the inner gradates also in irregular series. 



HiNDWiNG (pi. 2, fig. 1): Average length of female 4 mm., male 

 3.8 mm., width of female 1.5 mm., male 1.4 mm.; membrane hj^^aline 

 to yellowish; two prominent dark brown spots, the first larger (an- 

 tepterostigmal spot) and the second smaller (postpterostigmal spot); 

 faint brownish shading along about first four costal cross-veins; 

 center of pterostigma with long yellowish portion covering seven to 

 eight costal cross-veins; brownish veins include radial veins beyond 

 basal forking of R, MA, distal portions of MP, cubital and anal veins 

 (the basal portions of these veins and 1st m usually clear), the radial 

 and anal cross-veins, outer gradates, and basal sinuous piece of MA; 

 Rs usually forking into R2 + 3 and R4+5 at point basad of point of 

 coalescence of Sc and Rl; Cul with three to five branches reaching 

 margin; sLx outer gradates, including a sectoral cross-vein. 



Male genitalia (fig. 18,a-d) : Eighth tergite longer medio- 

 dorsally, tapering lateroventrally, not as broad as ninth tergite; 

 ninth tergite shorter mediodorsally and about as long ventrally and as 

 wide as tenth tergite; tenth tergite with mediodorsal border of each 

 half short, the ventrolateral border widened and prolonged distally; 

 ninth sternite with appearance of a pair of median laterally curved 

 processes extending distally from inner surface; two halves of tenth 

 sternite almost striplike, then turning inwardly and broadened ven- 

 trally, covered with coarse, toothlike, setae-bearing papillae; para- 

 meres with a more or less diamond-shaped flap projecting usually 

 anterodorsally from median plate, anterior margin heart shaped, 

 posterior hooks tripartite, largest process toward exterior, smallest 

 medial. 



Female genitalia (fig. 18, e) : Eighth tergite longer dorsally and 

 shorter ventrally, anterior margin more or less convex; ninth tergite 

 with each lateroventral half large, moderately elongate, anterior 

 margin broadest with slight indentation near dorsal border, dorsal 



