Wings.—Forewing semitransparent yellowish-brown., with darker brown pterostigma; male with a clearly marked whitish band crossing wing obliquely from about middle of R1 outwards and downwards to point of junction of 1A and 2A, and most strongly visible in cubital region, where veins are bent to run alongside it, and with a less clearly marked pale zigzag fascia descending from distal end of pterostigma across wing to end of Cu2; these markings are present in female also, but much less conspicuously. In male, the costa carries a series of black hairs, especially noticeable towards pterostigma, but these are absent in female. In both sexes there is a strongly marked patch of dark hairs at junction of 3A with 2A. Numerous short upright hairs are present on wing, those in distal half being very pale, those on basal half being pale also in female, Text-Fig. 7.—Neurochorema decussatum n. g. and sp., ♂. Appendages (× 50). a, lateral view; b, dorsal view. Note the crossed pre-auals. (10 per cent. KOH preparation.) but pale mixed with dark hairs in male, especially along Cu and its branches, where there are numerous dark hairs. Hindwing hyaline, iridescent, with pale yellowish-brown hairs distally, and pale fringe of same colour. Types.—Holotype male (Nelson, 5th October, 1920, A. Philpott), allotype female (20th October, 1920, A. Philpott), and series of five paratype males, taken October to November, 1920, by Mr. Philpott, at Nelson: all in Cawthron Institute collection. Habitat.—South Island of New Zealand, especially around Nelson. Other localities are Cass, Canterbury, and also around Invereargill. Probably widely distributed. Abdomen blackish; appendages of male yellowish-brown, pre-anals crossed as shown in text-fig. 7; in the dried insect they sometimes appear evenly more strongly crossed. Genus Hydrochorema n. g. (Text-fig. 8.) Allied to both Hydrobiosis and Hydrobiosella, but differing from both of them in the absence of Af1 in the hindwing, R2+3 being a simple vein without a terminal fork. It resembles Hydrobiosella in having both Af1 and Af2 of forewing sessile upon the closed radial cell, whereas Hydro-