158 CHLOEOPEELA CAPNOPTEEA n. Sp. 



margined with reddish (perhaps not so in the living insect). The 

 margin of the antepenultimate ventral segment ($) thickened , 

 raised and rounded in the middle. Tails black, but wholly yellow 

 in the basal third, with strong bristle-like hairs on the end of 

 each joint. 



"Wings uniformly pale smoky hyaline with the exception 

 of the costal margin which is yellowish. 



Anterior-wings long and narrow ; neuration in the apical half 

 fuscescent, but the costa and sub- costa are conspicuously yellowish 

 and the basal half of the cubiti with the rather numerous thicke- 

 ned veinlets in the two cubital areae, together with the anal 

 veins, are distinctly pale. 



In the posterior-wings the whole of the neuration is dark excep- 

 ting the costa and sub-costa, which are as in the anterior. 



Expanse 25 mm. (5). 



Hab. Osch, Turkestan. One $ in Albarda's collection. 



It is probable that all the pale parts may be more or less tinged 

 with greenish in lite. 



In our present state of knowledge it is hazardous to describe 

 new species of CJdoroperla, but this should be readily recognisable 

 by the peculiar colour of the wings, the anterior pair being also 

 unusually narrow. I do not remember to have seen the species 

 amongst those collected by Fedschenko , which were returned uni- 

 dentified. 



I take this opportunity of stating that the explanation of the 

 neuration of Perlidae given by Pictet (and followed by other authors) 

 is distinctly erroneous. His « nervure accessoire à la costale » is the 

 true sub- costa , whereas his « sous-costale » is the radius (or medi- 

 ana) ; in the same manner his « nervure accessoire à la sous-costale » 

 is the sector radii. 



As Pictet's work remains the principal systematic treatise on 

 the Perlidae , it "^is necessary to call attention to these discrepancies 

 in terminology. 



