88 NEW ZEALAND NEUBOPTEBA. 



which are then within the dried-up cocoons. It is,. 

 however, somewhat remarkable that this extensive and 

 constantly recurring destruction has not led to the 

 exclusive preservation of larvae endowed with an instinct 

 to fix their cocoons in deep water some distance from the 

 edge of the stream, but such a beneficial instinct does not 

 yet appear to have been universally produced. These 

 remarks will apply with equal force to Olinga feredayi, the 

 extensive annual mortality of which insect from the same 

 cause has already been noticed. 



Genus PSILOCHOKEMA, McLachlan (186(3). 



"Antenna? very slender, slightly longer than the wings. Head trans- 

 verse, produced in front between the antennae, rugose, the hinder portion 

 forming a raised collar. Ocelli very distinct. Maxillary palpi slender,, 

 slightly hairy, the two basal joints short and broad, the third longer and 

 slender, the fourth shorter than the third, the fifth longer than the third. 

 Mesothorax ovate, with a raised tuft of hairs in the middle in the male. 

 Legs moderately long, alike in both sexes ; spurs 2.4.4. Anterior wings 

 narrow, the margins nearly parallel, hairy clothing short and dense ; the 

 apex somewhat dilated ; on the cubital veins in the male are tufts of raised 

 hairs ; discoidal cell closed, with a smaller cell below it ; apical cells long 

 and narrow: apical forks present in all five veins. Posterior wings rather 

 shorter and broader; pubescence scanty; apical forks present in all five 

 veins. Abdomen moderately robust. 



"Distribution. — New Zealand. 



" In this genus the wings are nearly flat when in repose " (Hutton). 



PSILOCHOKEMA MIMICUM. 



Psilochorema mimicum, McLachlan, Trans. Ent. Soc. 

 London, ser. 3, vol. 5, p. 274 (1866). 



This species has occurred at Auckland, Wellington r 

 and Christchurch. It is fairly common in most situations 

 in the vicinity of water, and is a very pretty little insect 

 when alive. 



The expansion of the wings is about f inch. 



"Antennae fuscous, annulated with yellow, the apical portion wholly 

 fuscous. Head and mesothorax dark chestnut. Anterior wings smoky, 

 with pale golden and whitish markings ; a whitish indented fascia a little 

 below the apex ; several raised tufts of blackish hairs along the dorsal 

 margin towards the base. Posterior wings greyish-hyaline. Legs greyish- 

 ochreous, the tips of the tarsal joints annulated with pale yellowish. Ab- 

 domen blackish-fuscous, the appendages testaceous. In the male the 

 superior ajmendages are very small, slender at the base and clavate, hairy ; 

 inferior appendages very large and broad, concave and furnished with 

 numerous minute blackish teeth internally, the outer margin broadly 

 emarginate. Between the inferior appendages, on the superior portion, 

 arises a long flattened and obtuse piece, probably the upper penis-cover. 

 Length of the body, G$ mm. ; expanse of wings, 1(5 mm." (Hutton). 



