i8 9 3-] mz THE BRITISH- Nfr TURALIST. 



7 



common on leaves of Conyza squarrosa, at Grange-over-Sands ; and 

 Wocke gives " Central Europe, Russia (North, South, East and 

 West), Piedmont " {" Catalog,'' p. 344). 



Time of Appeara:\"ce — The species is single-hooded and occurs in 

 July and Angust, rarely before the second week of the former month. 

 Its date of emergence varies in different years, and depends largely on 

 the meteorological condition of each particular season. Stainton 

 gives " end of July and August. ' f 



Pterophorus, Wallengren, GeofTroy. 



This, the typical genus of the group, contains only one species 

 which is widely distributed throughout the Northern hemisphere, 

 in America, Europe, and extending into Armenia. When at rest 

 its name mono dactylus becomes very suggestive, as 'its wings are 

 rolled up on each side so as to form as it were " one " finger or wing 

 pointing in opposite directions. 



This genus is thus characterised by Wallengren : Antennae 

 rather long, those of the male finely serrated, of the female very 

 indistinctly ciliated, with the basal joint thickened. Forehead obtuse, 

 the feathers forming no cone. Palpi shorter than the head, slender, 

 rounded, somewhat ascending, pointed, with the joints not distinguish- 

 able. The tibiae all slender, not thickened. First pair of spines in 

 the posterior tibiae very unequal, the inner spine very long, being 

 more than double the length of the exterior one. Anterior wings cleft 

 to one-third of their length, the posterior angle in the anterior 

 segment wanting, in the posterior segment not very distinct. The 

 segments of the posterior wings slender, the posterior segments 

 without black scales in its very long fringes. The anterior margin of 

 the anterior wings defiexed, the posterior margin not toothed, with 

 the whole posterior segment both defiexed and turned in so as to form 

 a channel, in which the posterior wings are received when the insect 

 is at rest. Veins of the anterior wings, nine, of uniform thickness ; 

 the first from the base, almost in the very margin ; the second joined 

 at the base with the common lower trunk of the veins ; the third from 

 the posterior margin of the cell, and as well as the fourth, which is 

 t wo-branched, arises from the posterior angle of the cell, running into 

 the inferior segment ; the fifth to the seventh are simple, and arise 

 almost from the same place (the anterior angle of the cell), running 

 mto the anterior segment ; the eighth arises from the anterior margin 

 of the cell, and the ninth from the base. The veins of the posterior 

 wings are five ; the first, two-branched, arising from the anterior 

 angle of the cell, and running into the first segment ; the second and 

 third both simple, the second arising from the posterior angle, and the 



