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, 6 ; 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, 1.10 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, 1.00-1.10 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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