_Butterfly._--The male on the upper side is pale blue, with a narrow black marginal line and white fringes. The female is brown or lilac-gray, with a series of orange-red crescents on the margins of both wings. On the under side the wings are stone-gray, with the usual spots, and on the secondaries the orange-colored marginal spots are oblong, tipped inwardly with black and outwardly by a series of metallic-green maculations. Expanse, .90-1.15 inch. _Early Stages._--We know very little about these. It is found from Kansas to Arizona, and northward to Montana. (25) =Lycæna scudderi=, Edwards, Plate XXX, Fig. 48, ♂; Fig. 49, ♀; Plate V, Fig. 41, _chrysalis_ (Scudder's Blue). _Butterfly._--The commonest Eastern representative of the group to which the preceding four or five and the following three species belong. On the upper side the male cannot be distinguished from _L. melissa_; the female is darker and has only a few orange crescents on the outer margin of the hind wing. On the under side the wings are shining white, the spots are much reduced in size, the large orange spots found in _L. melissa_ are replaced by quite small yellowish or ochreous spots, and the patches of metallic scales defining them externally are very minute. Expanse, 1.00-1.10 inch. _Early Stages._--These are accurately described by Dr. Scudder in his great work, "The Butterflies of New England," and by others. The caterpillar feeds upon the lupine, and probably other leguminous plants. It is widely distributed through the basin of the St. Lawrence, the region of the Great Lakes, and northward as far as British Columbia, being also found on the Catskill Mountains. I have found it very common at times about Saratoga, New York. (26) =Lycæna acmon=, Doubleday and Hewitson, Plate XXXI, Fig. 27, ♂; Fig. 28, ♀ (Acmon). _Butterfly._--The plate gives a good representation of the male and the female of this pretty species, which may at a glance be distinguished from all its allies by the broad orange-red band on the hind wings, marked by small black spots. On the under side it is marked much as _L. melissa_. Expanse, .90-1.10 inch. _Early Stages._--Unknown. It is found from Arizona to Washington and Montana. (27) =Lycæna aster=, Plate XXX, Fig. 40, ♂; Fig. 46, ♀; Fig. 47, ♂, _under side_ (The Aster Blue). _Butterfly._--On the under side this species is very like _enoptes_ and other allied species. The male looks like a dwarfed specimen of _L. scudderi_. The female is dull bluish-gray above, with black spots on the outer margins of the wing, most distinct on the secondaries, and, instead of a band of orange spots before them, a diffuse band of blue spots, paler than the surrounding parts of the wing. Expanse, .95-1.00 inch. _Early Stages._--These furnish a field for investigation. The insect is reported thus far only from Newfoundland, from which locality I obtained, through the purchase of the Mead collection, a large and interesting series.