Feeeday. — Description of new Genera and Species of Psychidse. 261 



shade. Head and tliree first segments retractile. Tlie cases of full-fed 

 larvas vary in size from 1^ to 3^- inclies, long, narrow, and tapering, 

 colour varying from liglit to dark grey, generally smooth but sometimes 

 ornamented with pieces of twig or leaves laid on longitudinally in somewhat 

 regular order, inside thickly lined with fine brown silk. The case is 

 exceedingly tough. I have tested its strength and found that fracture takes 

 place at 32 lbs. The larva is found feeding on all kinds of trees and shrubs, 

 both evergreen and deciduous, not even rejecting the common laurel, and I 

 have named the insect omnivora on that account. I noticed it first on 

 willow trees, when I came to the colony in 1862. Willow, wattle, and 

 coniferous trees appear to afford a particularly favourite food. The cases 

 found on the willow and wattle are generally smooth and plain, but those 

 on the coniferous trees are frequently embossed with small pieces of twig 

 and foliage laid on longitudinally in an order that seems to indicate design. 

 Until fully grown the larva moves about with the case from leaf to leaf 

 feeding with its anterior segments and prolegs extruded. Attached to the 

 interior of the mouth of the case are silken threads which the larva, when 

 disturbed, draws so as to close the orifice. The larva before assuming the 

 pupa state fixes the case by repeated bindings of silk round a twig, as 

 shown in plate IX., on firmly attaching it to the trunk of the tree. The 

 larva whilst feeding suspends the case by a thread. The case is very small 

 at first, the larva commencing to form it soon after birth ; and, as the larva 

 increases in size, so is the case enlarged, the larva adding to it from time 

 to time as a mason builds a chimney. Fig. 1 represents a case fixed to 

 a twig of willow with the pupa skin extruded ; fig. 4, a case containing a 

 partly-grown larva as sus^Dended when at rest. 



Notwithstanding the security afforded by the case, a dipterous insect 

 (somewhat resembling a common bluebottle-fly, but not larger than a 

 common house-fly) is very destructive to the larva. I have found as many 

 as nine out of every ten cases filled with the cocoons of the fly. The fly 

 (fig. 2) is represented at rest on the case. 



I find the cases have become much less common in my garden than 

 formerly, which I attribute to the increase of bu-ds. 



Fig. 3 represents a x^ortion of the branch of a larch fir, with a case of 

 this insect attached. The silk wound round the branch prevented the 

 return of the sap, and caused an extraordinary swelling of the upper part 

 of the branch. It was found by Mr. James Townsend, at Christchurch. 



Okophoka, n.g. 

 [From 6po(pri " thatch," and (jyopelv " to bear," aUudiug to the case being covered 

 with pieces of grass in the manner of thatch.] 



Male. — Body stout, extremely lanate ; head small, not prominent; palpi 



