«6 NEW ZEALAND NEVROPTEBA. 



in the North Island, and at Nelson and Christchurch in 

 the South Island. It is probably common and generally 

 distributed throughout New Zealand. 



The expansion of the wings is 1 inch. The fore-wings in the male are 

 •dull yellowish-brown ; there is a chitinous fold running from the base along 

 the dorsum, and curving upwards parallel to the termen ; the hind-wings are 

 dusky. The female has the fore-wings golden-yellow without any chitinous 

 fold. 



The larva of this insect is extremely abundant in most 

 running streams. It constructs a perfectly smooth, light 

 brown, semi-transparent, and slightly curved cylindrical 

 case, made entirely of a glutinous material secreted by the 

 insect. These cases are to be found in the streams during 

 the entire year, but many of those taken about December 

 are very small, apparently indicating that the larva 

 chiefly grows during the late summer, autumn, and winter, 

 usually becoming mature in the spring. Some full-sized 

 cases are, however, always to be found, and prolonged 

 investigations prove that the successive broods of this 

 insect must overlap one another to a very great extent. 

 A glance at the table on p. 98 will show how largely these 

 larva? contribute towards the food supply of our trout, and 

 as both the case and the contained larva are devoured, 

 no difficulty is experienced in identifying with absolute 

 certainty the numerous specimens, which are found 

 during an examination of the contents of the stomachs 

 of those fish. 



The length of the larva, when full grown, is about g inch, that of its case 

 being about h, inch. The head and first segment of the thorax are very 

 horny, and bright reddish-brown in colour. The anterior legs are short and 

 very stout, the two other pairs are rather long and much slenderer. The 

 remaining segments of the body are very large, soft, and bright green in 

 colour. The two terminal segments are slightly paler. The last segment 

 has two very large protuberances fringed with bristles and furnished with a 

 pair of very small claspers. 



This. larva is very active, climbing amongst the stones 

 in rapid streams with great agility. When full grown it 

 fastens the posterior extremity of its case firmty to a 

 stone, and closes the free end with a tight-fitting lid. 

 These fixed cases are usually found in groups, comprising 

 twenty or thirty individuals, attached close together on 

 the under side of a single boulder. This habit of congre- 

 gating in groups for purposes of pupation is very remark- 

 able, and probably serves some useful purpose, though at 

 present it is difficult to say in what way it is beneficial to 

 the insect. 



