Genus Thanaos 



the under side as a series of pale-yellowish spots more or less 

 distinct. The hind wings have a double series of faint yellow 

 spots; these as well as the marginal spots of the primaries are 

 very distinct on the under side. Expanse, i. 25-1. 60 inch. 



Early Stages. — The caterpillar feeds on oaks, Galactia, and 

 possibly Baptisia. The life-history has been only partially ascer- 

 tained, in spite of the fact that the insect has a wide range and is 

 not uncommon. 



Bri\0 occurs from the Atlantic to the Pacific, ranging from the 

 latitude of New England to that of Arizona. 



(2) Thanaos icelus, Lintner, Plate XLVIII, Fig. 17, $ ; Plate 

 VI, Fig. 27, chrysalis (The Dreamy Dusky-wing). 



Butterfly. — Prevalently smaller in size than the preceding spe- 

 cies. The under side of the wings is paler than the upper side, 

 and the outer third of both the primaries and secondaries is 

 marked with a profusion of small indistinct yellow spots, which 

 do not form well-defined bands as in the preceding species. On 

 the upper side of the fore wing the median area is generally 

 marked by a broad band of pale gray, but this is not invariably 

 the case. Expanse, 1. 00-1.20 inch. 



Early Stages. — These have been described by Scudder. The 

 caterpillar feeds on a variety of plants, as the aspen, oaks, and 

 witch-hazel. 



Icelus ranges across the continent from Nova Scotia to Oregon, 

 and south to Florida and Arizona. 



(3) Thanaos somnus, Lintner, Plate XLVIII, Fig. 2, $ (The 

 Dark Dusky-wing). 



Butterfly. — A little larger than the preceding species, espe- 

 cially in the female sex. The male is generally quite dark, the 

 banding of the fore wing on the upper side obscured. The hind 

 wings have a row of light marginal and submarginal spots, more 

 distinct on the under side than on the upper. The female gen- 

 erally is light gray on the upper side of the wings, with broad 

 median and submarginal bands of dark brown, tending to fuse or 

 coalesce at a point near the origin of the first median nervule. 

 Expanse, $, 1.25 inch; ?, 1.50 inch. 



Early Stages. — But little is known of these. 



All ofthespecimens I haveeverseencamefromsouthern Florida. 



(4) Thanaos lucilius, Lintner, Plate XLVIII, Fig. 10, $ ; 

 Plate VI, Figs. 30-32, chrysalis (Lucilius' Dusky-wing). 



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