555 



REVISION OF AUSTRALIAN LEPIDOPTERA, V. 



By a. J. Turner, M.D., F.E.S. 



Fam. GEOMETRID.E. 



Subfani. GEOMPiTRINiE. 



Forewings with 7, S, 9 stalked, 10 usually stalked with them, 

 their common stalk arising from upper angle of cell, 6 nearly 

 always approximated or st^dked with them, 11 usually separate, 

 rarely stalked, either free or anastomosing shortly with 12 and 

 10, or with 12 only, no areole. Hindwings with 5 strongly 

 approximated to (i at origin, 8 approximated to cell near base, 

 diverging at or before middle, or rarely approximated to beyond 

 middle. Frenulum and retinaculum frequently rudimentary or 

 absent, being replaced by a rounded costal dilatation of base of 

 hind wing. 



The Geomeirince form a very natural group. The Acidaliance 

 (or Sierrhince) are usually, though not always, distinguisliable by 

 the origin of vein 5 of the hindwings. But independently of 

 this, the structure of the forewings is fundamentally different in 

 the two subfamilies. In the Acidaliance, veins 11 and 10 arise 

 by a common stem, which anastomoses with the common stem of 

 7, 8, 9, forming the ai eole. Those genera in which the areole is 

 absent, have been developed from genera in which that structure 

 exists, by the gradual obliteration of the areole by fusion of its 

 walls. In the Geometrincc, on the other hand, an areole is never 

 developed ;■'>' vein 11 is either free, or very frequently anastomoses 

 first with 12 and tlieu with 10, or it may anastomose with 12 



* My attention was called to this point byHampson's " Moths of India," 

 iii., p.466; but Mr. Prout informs me that the absence of an areole in this 

 group was first insisted on by Lederer. 



