NORTH AMERICAN LEPIDOPTERA. 131 



twice as long and stout as the anterior ; median tibia with a single 

 pair of unequal spurs at tip ; posterior with two pairs of longer, un- 

 equal spurs. Anterior tarsi with a row of stout, curved spines out- 

 wardly, most prominent in lineata. 



Primaries with eleven veins, the cell short ; outer margin arcuate, 

 entire, obliijue ; apex acute ; hind margin very little sinuate. Prof 

 Fernald says the primaries have sometimes twelve veins ; none of 

 the sjjecimens examined by me had more than eleven, but it is not 

 unlikely that 9 does occasionally branch ; in such case vein 10 nuist 

 be very difficult to see, except by fully denuding the wing. Secon- 

 daries with 2, 8 and 4 nearly equidistant at base ; 5 midwav from 

 the cross-vein. The margin is entii'e, except for a slight projection 

 on vein lb. 



The genitalia of the male have the su{)ra-anal plate produced into 

 a short, abruptly pointed and slightly curved hook ; the inferior pro- 

 jection nearly as long as the superior, but thicker, the tips blunt. 

 Side pieces enlarging somewhat toward tip, then rather suddenly 

 rounded off, the angle rather inferiorly. From the inferior margin 

 near the base arises a single corneous hook, differing somewhat in 

 form in the two species. 



The European fauna is rich in forms in this genus, while in 

 America but two species are found. They have a habitus all their 

 own, and are consequently recognizable at a glance whenever a sin- 

 gle typical form has been once carefully observed. 



Two species are known from our fauna, one of which is claimed 

 as identical with Euro])ean forms, viz., chamcenerii with gallli. This 

 question will be more fully discussed hereafter. 



Chamcenerii has the spinules of tibia less marked, the abdomen 

 more abruptly conic, the thorax immaculate on disc, the veins of 

 primaries not white lined. 



Lineata has the tarsal armature much heavier, the abdomen more 

 elongate, the thorax with longitudinal white lines ; primaries with 

 veins white, marked. 



D. gallii Eott. Naturf. vii, 107; Wlk., C. B. M. Lep. Het. viii, 166; Clem.,* 

 Journ. Ac. N. Sci. Phil. iv. 1859, 144 ; Bd., Lep. Cal. 66 ; G. <fe R., Pr. E. S. 

 Ph. V. 156; Tr. A. E. Soc. ii, 75; Strk., Lep. Rhop. et Het. 79; Bd., Sp. Geu. 

 Het. i, 169 ; Biitl., Tr. Zool. Soc. Loud, ix, 569. 



chamsenerii Harr.,* Sill. Journ. 36, 305, Deilephila ; Ag., Lake Superior, 387. 

 pi. vii, fig. 2; Wlk., C. B. M. Lep. Het. viii, 167 = gallii ; Morr.,* Syn. 1862, 

 165, Deilephila; Harr., luj. Ins. 328; Lint.,* Pr. E. S. Ph. iii. 660, Deilephila ; 



