OF NORTH AMERICA. 229 



Genus PLATYCERTTRA. Packard. 



" Head large and prominent, twice as large as in Cerura ; front scu- 

 tellate, broad between the antennae, while the sides are more parallel 

 than in Cerura. Scales short and fine. Palpi short, a little depressed, 

 not reaching the front, compressed and slender ; the 3rd joint short, 

 obtuse. Antennas longer than in Cerura, very narrowly pectinated ; 

 joints longest in the middle, but slowly decreasing in length towards 

 the tip, which is almost simple. Thorax stouter than usual, no "col- 

 lar " or transverse lines. 



"Primaries short broad triangular, half as broad as long. Costa 

 straight, curved down more than usual at the obtuse apex ; outer edge 

 short and not so full as usual ; inner angle much more rectangular 

 than usual, while the inner edge of the wing is very nearly straight, 

 though not much longer than the outer edge. 



"The I St subcostal is placed much within the middle of the wing. 

 There is an intercostal space. 2nd subcostal arises just within the ori- 

 gin of the 3rd subcostal. The apical interspace is of the size of that 

 in Cerura, while it is, owing to the curved nervules enclosing it, semi- 

 ovate and not triangular as in Cerura. The 4th and 5th subcostals 

 are short and straight : The ist median nervule instead of being an 

 independent as in Cerura, is curved downwards at the base, and united 

 with its main nervure, and the 4th median is straight. 



" Secondaries short and rounded, apex very obtuse. They reach to 

 the outer fourth of the abdomen. Thus it is much shorter and broader 

 than in Cerura. The apical interspace is long, much as usual. 



"The abdomen tapers rapidly, contracting rapidly before the tip 

 which is well tufted. Legs much as in Cerura. 



"The broad triangular fore wings, orbicular secondaries and large 

 broad closely cropped front, the short acute abdomen, and long pecti- 

 nated antennae, distinguish this genus from Harpyia of Europe, which 

 it somewhat approaches.'' 



Packard, Proc. Ent. Soc. Phil. III. p. 373. (1864. 



