Tittyarp.—Studies of New Zealand Trichoptera. 305 
Genotype.— P hilorheithrus agilis (Hudson). (New Zealand.) 
Two species of this genus are known from New Zealand, one of which 
is here described for the first time. There are also to be found in eastern 
Australia and Tasmania closely similar insects, none of which have so 
far been described. 
Philorheithrus agilis (Hudson). (Plate 19, fig. 9; text-figs. 17-19.) 
In size this is one of the most variable insects known to p E AED 
specimens in the Cawthron Institute collection vary from 21 mm. 
37 mm. in expanse, and the male is almost as variable. The Tein of É 
wings and the distinctness of the тана ра re also very variable. 
pid ges appear so omewhat бв forcipate) ; and eM 17 shows the 
venation of the miale, that of the female wed BUM the same. 
TrxT-F1G. 19.—Philorheithrus agilis (Hudson), +. es (x 30) a, dorsal 
view; b, lateral view. Note the strongly А кыз журш pre-anals. (10 per cent. 
KOH preparation.) 
Type in Mr. G. V. Hudson's ‘collection (sex not stated; probably a 
male). 
tat.—Provinces of Wellington, Nelson, and спре: ; local, but 
abundant in places; found on fast-running mountain-stre 
Philorheithrus lacustris n. sp. (Plate 19, fig. 10.) 
d. Total length, 8 mm. ; forewing, 14mm.; expanse, 29 mm. 
Morphologically very close to Ph. agilis (Huds. ), from which it may 
at once be distinguished by pointed apex and evenly-rounded termen of 
forewing, much more elongated hindwing with narrowed apex, stronger 
arching of costa of ача. near base, absence of any definite colour- 
pattern on wing, forewings being a dull medium fuscous, darker towards 
apices, with a slightly paler mark on pterostigma, hindwings semitrans- 
parent greyish, tinged се pink along costal margin. Appendages 
rather similar those of Ph. is, pre-anals forming a stout forceps, but 
ecu inue not projecting at all as in that species, and excessively short. 
Ф 
