TiL.LvARD.—Studies of New Zealand Trichoptera. 293 
biosis has Af, sessile but Af, stalked. It also resemble Hydrobiosis in the 
form of the tw o median forks, Af, being a very long fork with short stalk, 
Af, а. бш Каб shorter fork with stalk about as long as the fork itself ; 
in H ydrobiosella these two forks are both short terminal forks with very 
long stalks. The structure of the cubitus in the forewing is very similar 
to that in Hydrobiosis—i.e., considerably more specialized than in Hydro- 
biosella, where the large fork of Cu, is free and of primitive dichotomic 
form. -Anal area of forewing with both 2А and ЗА well developed, the 
former joining 1A at the bend of Cu, just below point where Cu, € 
and the latter extending a little beyond half-way from base to this poin 
Pterostigma of forewing well developed, with R, running through it as a 
loop. Sc running alongside or fused with R, in forewing, separate from. 
it in hindwing, but very short, ending up before half-way along costa. 
Hindwing with Af, apparently forked, but position of wing-spot, placed 
apparently in angle between R,., and R,., at their origins, would 
Cu, 
Text-ric. 8.—H ydrochorema crassicaudatum n. g. and sp., 4 Wing-venation. 
(For lettering see p. 314.) - 
appear to indicate that there has been a suppression of the extra cell to 
be descri in next genus; in this case the genus Hydrochorema would 
show a more highly evolved state of the radial sector in hindwing than does 
ema, though the same region remains more primitive in forewing. 
General shape of. wings rather long and slender, the forewing gradually 
widening from base outwards to end of n stigma, and then narrowing 
quickly to form a bluntly-pointed apex on R,.  Hindwing with apex at 
R,, but practically in line with costa. Tibia spurs, 2, 4, 4. Male with 
long, forcipate gonapophyses 
Genotype.—H ydrochorema crassicaudatum n. sp. (New Zealand.) 
Hydrochorema crassicaudatum n. is (Plate 19, fig. 5; text-figs. 8, 9 b, 
10 a.) 
d. Total length, 4 mm.; forewing, 6-7 тт; expanse, 14 mm 
Head brown, very hairy; eyes dark brown : antennae nearly as long 
as forewing, medium brown, with tuft of dark hairs below bases; colour 
of antennae darkening towards tip, and all segments very lightly annulated 
with darker brown ; maxillary and labial palpi dull-brownish. 
