MEMOIRS OF TPIE NATIONAL ACADEJIY OF SCIENCES. 



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scales. Eyes nalccil. Aiiteiiiiiv well i)ectinateil on tlie basal two tliirds. beyond Ulitorm; the 

 brauches more or less ciliated; the joints above uotdenselj' scaled. Palpi imieli larger and rather 

 wider than usual, stout, ascending', reaching a little beyond the front; second Joint longer than 

 the first and rather longer than usual; the scales on the upper side short and <lense, below much 

 longer and uneven; third Joint conical, often rather short, snuill, not always very distinct, being 

 more or less couceakd by the long loose hairs of the second joint. 



Maxilhe longer than usual and very well develoi)ed, forniiug several coils. Thorax not 

 crested. Fore wings rather less than one-half as long as broad; costa nearly straight or slightly 

 convex ; apex somewhat rounded or pointed or (in hydronieli) squarish, (in nnicolor abruptly bent), 

 but usually somewhat produced; outer edge long, oblique, convex (in vnicolor sharply bent on 

 first cubital venule, III;). Hind wings shorter and more rounded at the apex than in any other 

 genus of the family, outer edge shorter, more regularly rounded than usual; costal and inner edge 

 of nearly the same length. Wings not tufted. 



JTIG. 80. Venation of Heterocampa obliqua; tbo names of the veins as desi;inatecl on p.&6; d, 



aiiteiior; d', posterior discal vein; /, frenulum ; sc, subcostal eell. 



Venation much as in Schizura, but quite variable; usually a long narrow subcostal cell, 

 though it is sometimes open in individuals of the same species; the third subcostal venule is very 

 short, and the cell between it and the fourth is minute; in the siiperba and hydromeli group the 

 subcostal venules tend to be bent up at their end toward the costa, and so in rt.s^fc/cand hiundata, 

 but usually they are diverted more toward the apex, and then more parallel with the costa; the 

 discal venules vary in length and direction; the anterior one is usually short and diverted 

 obliquely inward to where it meets the sixth venule; the hinder discal venule either forms a 

 regular curvilinear line, or is broken into two portions forming an angle witli the apex, pointing 

 inward, from which the median discal fold passes to the base of the wing ; the first cubital vein 

 (III.) usually more or less detached at its origin from the second and at the bend throwing ofi'the 

 hinder discal venule (d'). 



Hind wings with the venation quite uniform, the first and second subcostal venules separating 

 a short distance beyond the origin of the anterior discal venule, the fir.st being a little shorter than 

 the second branch (in maiitco the second originates halfway between the first and the independent) ; 



