92 NEW ZEALAND NEUBOPTEBA. 



They are usually commonest in the late summer, when 

 the rivers are generally very low, and in consequence a 

 luxuriant growth of the green slime weed is present. 



This caddis-fly must be tolerably common during the 

 summer, but owing to its small size would not be likely 

 to attract attention. I have seldom observed it in a 

 state of nature, my specimens having been reared from 

 the larva. 



Another larva, closely related to the above insect, 

 which feeds on the same green weed, is figured, much 

 magnified, on Plate IX., fig. 11. This species constructs 

 an oval case, which is always kept in an erect position. 

 Both of its apertures are identical in size and shape, and 

 are employed quite indifferently by the larva, which 

 projects itself sometimes from one end of its abode and 

 sometimes from the other. When mature this larva 

 fixes its case to a stone by its edge, always keeping it in 

 a vertical position, and employing for this purpose two 

 strong bands of viscous material. Whilst engaged in 

 thus anchoring its dwelling, the larva extends itself from 

 the case' through each of the above-described orifices. 



The caddis-fly, which results from this larva, is 

 undescribed at present, but as it is very inconspicuous 

 and closely resembles O. albiceps in general appearance,, 

 the chief interest of the insect will always centre in its 

 preparatory stages. 



