Lepidoptera of New York and Neighboring States 417 



and oblong, tli8 outer margin typically smoothly rounded, but often concave 

 in the middle, with M 1 to CUj approximate toward margin. Apex rounded or acute, 

 never strongly falcate, but occasionally subfalcate. All veins separate, the separa- 

 tion between M 2 and M 3 at base well marked. Male with a well-developed costal 

 fold; so far as examined, containing a hair pencil. Hind wing trapezoidal, normal, 

 without sexual modification; R and M t normally approximate at base, never 

 separate; M 2 almost connate at origin with M 3 and Cu l3 which are stalked, or rarely 

 united. 



Larvae usually borers in the stems or roots of herbaceous plants, especially 

 Compositse. 



The genus is too large and rather heterogeneous, but attempts to divide it 

 have, so far, not been very successful. Presumably several genera are derived 

 from it by the loss of the costal fold. 



The following key to species must be used with caution, as many species, 

 especially of Epiblema, run very close. Females of Thiodia and related genera 

 must also be watched for; a few of these are included in this key for convenience. 



Key to the Eucosmince with costal fold 



1. With extensive silver or pure white areas 2. 



J . Not largely silvery or pure white 6. 



2. Fore wing silvery with a brown St. Andrew's cross. . . .6. Eucosma adamantana. 



2. Fore wing with more complex markings 3. 



3. A transverse median or antemedian silver fascia 4. 



3. A longitudinal silver streak from base to end of cell 5. 



3. Basal half white, with an incomplete brown fascia 29. Eucosma grotiana. 



4. With an upright silver bar between the small basal spot and the fascia. 



8. Eucosma robinsonana. 



No spot between the basal one and the fascia .... 7. Eucosma quinquemaculana. 

 A single silvery costal median spot, extending beyond the end of the streak 



along lower edge of cell 9. Eucosma ridingsana. 



An antemedial spot, almost reaching the base on the costa, as well as the 



medial one 11. Eucosma hipeana. 



A single median costal patch, joined before the middle of the wing to the 



streak 10. Eucosma argentifurcatana. 



Ground color largely bright green 9. Epinotia medioviridana. 



8. Without green 7. 



Speculum with a group of regular rows of black spots 8. 



7. Speculum with three or four streaks or spots, or absent 13. 



8. Area above speculum evenly buff 1. Eucosma circulana. 



8. Area above speculum dusted with black or brown. 9. 



9. Base of fore wing evenly yellow, not dusted 10. 



9. Base of fore wing, at least along inner margin, dusted with brown 12. 



10. With transverse silvery gray bands toward base 5. Eucosma fraudabilis. 



1 0. Base wholly yellow 11. 



11. The area above the speculum, enclosed in a broken lead-colored circle, almost 

 wholly dusted with brown Thiodia annetteana. 



11. Less than half of this area dusted with brown Thiodia refusana. 



12. Ground of apical half, and a streak in cell almost to base, yellow, not dusted. 



2. Eucosma scintillana. 



12. Wing almost wholly dusted with brown 3. Eucosma dodecana. 



12. Basal fourth dusted with brown, contrasting 4. Eucosma fratruelis. 



M 3 and CUj of fore wing becoming coincident at outer margin. 



19. Eucosma cataclystiama. 



13. M 3 and Cu x separate 14. 



14 



