30 NEW ZEALAND NEUBOPTEBA. 



If disturbed, however, it flies with considerable rapidity,, 

 and at this time the female especially is very con- 

 spicuous ; its bright yellow wings, with black bands, 

 giving it, when flying, a most striking appearance. As 

 a rule the sub-imago is seldom seen in a state of nature, 

 and can only be obtained with any degree of certainty 

 by rearing individuals from the larva. The perfect 

 insect appears from the beginning of December until 

 the end of January. In some localities it is very 

 common at evening dusk, and its large size and cha- 

 racteristic vertical flight render it a conspicuous object 

 when projected against the bright background of the 

 evening sk} r . At such times the long tails of the males 

 can clearly be seen hanging downwards from the insect,, 

 thus presenting a most graceful appearance. The 

 females are not nearly so common. They fly much 

 closer to the ground than the males, and on this account 

 alone they are much more difficult to obtain. This 

 May-fly is not often found in the daytime, although,. 

 on rare occasions, I have dislodged male specimens from 

 amongst foliage on the margins of streams. 



In the Entomologist's Monthly Magazine for December, 1894, page 271, 

 Mr. McLachlan thus alluded to the peculiarities exhibited by this insect : 

 "A very remarkable species in coloration, and still more remarkable for 

 the condition of the median caudal seta as exhibited in the male and female 

 sub-imago in my collection ; such a condition, if constant, being probably 

 sufficient for generic separation, showing relationship with Heptagenia on 

 the one hand, and Pentagenia on the other." Subsequently (in 1899) the 

 genus Ichthybotus was founded for its reception by Mr. Eaton. 



Genus ATALOPHLEBIA, Eaton (1881). 



Imago. — Pronotum of the female with a longitudinal median ridge.. 

 Hind tibiae generally longer than the femora and longer than the tarsus ; 

 tarsal claws all narrow and hooked. Middle caudal seta generally deve- 

 loped. Hind-wings more or less obtusely ovate, with costal and sub-costal 

 nervures much arched, the radius nearly straight ; transverse nervules 

 abundant in the fore-wing ; those in the marginal area, before the bulla, 

 well defined. Forceps basis of male either entire or at most merely 

 emarginate in the middle of its apical edge. 



Sub-imago. — Quiescent during many hours, standing upon all its feet, 

 with the wings erect, and with the lateral caudal setae spreading. 



Distribution. — Australasia, Japan, Ceylon, South Africa, South America.. 



ATALOPHLEBIA VERSICOLOR. 



(Atalophlebia versicolor, Eaton, Trans. Ent. Soc. 

 Lond., 1899, p. 286.) 



This species is common in the Wellington district, but 

 has not been recorded from any other locality at present. 



