224 BEVISION OF THE FAMILY EUSTHEXIIDAE (ORDER PERLARIA ) , 



Family EUSTHENIIDAE. 

 Key to the Subfamilies. 



1. Wings very short and broad, the forewing less than twice as long as broad; 

 Ms in forewing very strongly formed, making an acute angle with M1-4 dis- 

 tally. Costa of forewing strongly dilated basally. Branches of Rs arising 

 from R as a pectinate series of apparently separate sectors. 



TuAuMATOFKRLiNAK, n.subfam. 

 Wings not exceptionally short and broad, the forewing always more than twice 

 as long as broad. M.'-, less strongly formed, making either a right angle or an 

 obtuse angle with M1-4 distally Costa of forewing not dilated ba.sally. Branches 

 of Rs in fonewing dichotomic, arising normally from Rs 2 



2. Stoutly built insects of red or purple colouration, the forewing less than 

 thrice as long as broad. Cerci long, from 12 to 16 mm., 



EnsTHENiiNAE, n.subfam. 

 Much more slenderly built insects of green, yellow, brown or grey colouration, the 

 forewing about five times as long as broad. Cerci short, from 5 to 8 mm. 



Stenopeklinae, n.subfam. 



Subfamily THAUMATOPERLINAE, n.subfam. 

 Genu.s T h a u m a t o p e r l a, n.j;-. (Plate xi., fig. 1.) 



Characters as given in the key for the subfamily, with the following addi- 

 tions: — Antetniae with fifty or more joints, the basal joint much enlarged. Maj:il- 

 lary palpi five-joiuted, tiie basal joint a mere ring, the other four broad and 

 flattened, the second being very short, the third longer, broad and femur-like, the 

 f(jurth lunger iind narrower, the distal joint shorter and narrower still, with 

 rounded apex. Labial palpi three-jointed, the basal joint very short, the second 

 fairly long, broad and flat, the third shorter and narrower, with rounded apex. 

 Pronotum more than half as wide again as long. Legs with the femora very 

 broad and strongly built, the tibiae long and rather slender, the tarsi hairy, the 

 third joint long and club-shaped, carrying strong claws and a well developed 

 euipodiura. Ahdomrii about as long as forewing, broad and rather liattened; the 

 cerci stoutly built, of moderate length, with at least fifteen joints. 



To the venational characters given for the subfamily may be added the 

 following: — In the forewing, the dilated basal portion of the costal space is 

 free of eross-\eins for a short basal space, but distally from this it carries a 

 double row of cellules. The "apparent" sectors of the radius arc three to four 

 in niuiibcr, \cry irregular in form and position. M is completely fused with 

 R basally for more Mian one-fourth of the wing-length; immediately on leaving 

 R. it divides into M1-4, descending obliquely across the middle of the wing, 

 parallel to the radial sectors, and into M5, a very stoutly formed vein running 

 quite transversely across the wing, at right angles to R-|-M, to join Cut just 

 distad from its origin from Cu, and thus forming a very conspicuous cubito- 

 median Y-vein, of which the ujiper arm is more than twice as long ;is the lower. 

 Cu and lA are fused basally for about half the distance that K and M are fused. 

 After junotioning with M.-,, Cui is a strong convex vein; it has a long distal 

 fork. CuL' remains concave and lies for the most part in the cubito-aiuil groove, 

 but its distal end is free from this groove, lying anterior to it. lA, immediately 

 after leaving Cu, is connected with 2A by a strongly formed transverse vein at 

 right angles to it ; 1 A is a convex, wavy vein, with a short distal fork. 2A and 

 3A are both irregularly \\avy, forked veins. 



