20.2 CONNECTICUT GEOL. AND NAT. HIST. SURVEY [BuU. 



Genus Didymops Rambur 



N5miphs. — With frontal horns ; hind angles of head obtusely 

 rounded, not angulate; mental setae seven, five lateral setae; 

 abdomen with dorsal hooks ; lateral spines of segment 9 as long 

 as that segment. 



Adults. — With arculus sectors united for some distance beyond 

 arculus ; triangle free ; subtriangle present, the cubito-anals usually 

 three in number ; area between M4 and Cu^ widened at margin 

 of front wing ; base of the wings inf uscated ; eyes contiguous 

 in a single point only ; no elongate forked process on segment 8 

 in the female ; abdomen gradually contracted behind the second 

 segment and strongly compressed ; color not metallic, usually dull. 



Didymops transversa (Say) 



Journal of the Academy of Natural Sciences of Philadelphia, 8: 19: 

 1893. 



Njonph (PI. IV, Fig. 5). — Color dark and light brown. 



Head: labium extending between the middle and hind coxae, 

 mentum a trifle longer than broad, conspicuously contracted at 

 base, with 5 to 6 long setae on each side, and a number of smaller 

 ones between the two series ; distal margin of the mentum spinose ; 

 labial palpi (Fig. 7, No. 9) with 6 teeth on mesal margin, the 

 teeth with minutely crenulate margins and 3-4 unequal long spines 

 at their apices ; 5 lateral setae on each palpus and an additional 

 one near the lateral articulation, the dorsal margins also with a 

 row of smaller setae ; labrum setose below ; antennae /-seg- 

 mented, segments i and 2 thicker ; 3-7 subequal in length, a single 

 prominent frontal horn between the antennae, the horn provided 

 with a few long setae, and densely spinose, with minute spines 

 above ; caudo-lateral margins of the head with blunt tubercles. 



Thorax: legs spotted, the femora with three dark bands, and 

 small spots between ; tibiae spotted, the hind femora mostly brown ; 

 tarsi and claws brown ; hind femora when extended parallel to 

 the body reaching the caudal margin of abdominal segment 9; 

 pronotum with a curved caudal ridge connected with lateral promi- 

 nences ; a single rather broad, triangular plate over the procoxae 

 projecting cephalad ; wing-pads (immature specimen) extending 

 beyond the base of abdominal segment 6. 



Abdomen: broad, flat below (almost circular in ventral view) 

 the dorsal surface mottled with brown; lateral keels with spines 

 on segments 8 and 9, those on 9 extending slightly beyond the 

 tips of the appendages (equal or very slightly shorter in some) ; 

 prominent dorsal hooks present on segments 2-9, those on 6-7 

 largest; terminal appendages subequal in length, the ventrals 

 slightly longer. 



