Genus Thecla 



brown, covered with very short bristly hair, the wing-cases 

 paler." The food-plant is unknown. 



This species is boreal in its haunts, and is found in New Eng- 

 land and northward and westward into the British possessions. 



(30) Thecla irus, Godart, Plate XXX, Fig. 12, $ ; Plate V, 

 Figs. 32-34, chrysalis (The Hoary Elfin). 



Butterfly. Grayish-brown on the upper side. The wings on 

 the under side are of the same color, paler on the outer margins, 

 and darker toward the base. The species is subject to consider- 

 able variation. The variety arsace, Boisduval, has the hind wings 

 marked with reddish near the anal angle, and the outer margin 

 below marked with hoary-purple. The usual small crescentic 

 spots appear on the outer margin of the hind wings, or they may 

 be absent. Expanse, 1. 1 o inch. 



Early Stages. An epitome of all that is known is to be found 

 in "The Butterflies of New England." The caterpillar feeds on 

 young plums just after the leaves of the blossom have dropped 

 away. 



The species is rather rare, but has been found from the Atlan- 

 tic to the Pacific in the latitude of New England. 



(31) Thecla henrici, Grote and Robinson, Plate XXX, Fig. 21, 

 $ (Henry's Hair-streak). 



Butterfly. Much like the preceding species on the upper side, 

 but with the outer half of the wings broadly reddish-brown. 

 The secondaries on the under side are broadly blackish-brown on 

 the basal half, with the outer margin paler. The division be- 

 tween the dark and light shades is irregular and very sharply 

 defined, often indicated by a more or less perfect irregularly 

 curved median white line. Expanse, i.oo-i.io inch. 



Early Stages. These have been described by Edwards in the 

 " American Naturalist," vol. xvi, p. 123. The habits of the larva 

 are identical with those of the preceding species. 



It occurs from Maine to West Virginia, but is rare. 



(32) Thecla eryphon, Boisduval, Plate XXX, Fig. 17, $, 

 under side (Eryphon). 



Butterfly. Closely resembling the following species both on 

 the upper and under side of the wings, but easily distinguished 

 by the fact that, on the under side of the fore wings, the inner of 

 the two dark bands on the outer third of the wing is not sharply 

 angulated below the third median nervule, as in T. niphon, but is 



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