We have therefore in these separated districts two apparently good species, answering to any definition of that name. But between, there is a belt of latitude passing through New York and southern New England, where in one section or other both types are found and the whole series of intergrades. In this belt Alope and Nephele are found to be dimorphic forms of one and the same species. I formerly was of the opinion that they were distinct species, though in some districts there were intergrades. I thought these approaches of one to the other did not bridge the whole space between. In a paper printed in Proc. Ent. Soc. Phil, 1866, I gave my reasons therefor. But some observations made in July, 1876, at Martha’s Vineyard, led me to suspect a closer relationship between the two species or forms. In the open country back of Oak Bluffs, I found these butterflies fresh from chrysalis, and in considerable numbers. They were all very black, diminutive, and there was every grade from what I had been in the habit of calling Nephele to unquestionable Alope, with a broad clear-colored band. The band was not yellow, however, as in the typical Alope, but reddish-yellow like that of Pegala, which Fabricius called rufa in distinction from flava, applied to Alope. Mr. Scudder took the same small reddish-banded form on Nantucket, which island is about 30 miles from the mainland, Martha’s Vineyard being about 7. I call this variety Maritima, but whether it is restricted to the islands, or appears on the adjacent coast, I am not yet advised. Mr. Mead obtained for me a large number of eggs of this butterfly, while at the Bluffs shortly after my departure. They were laid by the broad-banded females in confinement and mailed to Coalburgh. There the larvæ hatched out, and these as well as the eggs were found to be precisely like the same stages of Nephele from Catskills. But none of the larvæ survived the winter.
In the belt spoken of, Nephele rather keeps to the highlands. It is the prevailing form in the Catskills, if with it are classed the intergrades, but full-banded Alope may be taken in small numbers every season. Along the Hudson River, Alope is the common form, but I have received intergrades very near to Nephele from Mr. Hulst, taken at Hoboken, N. J.; and a black Nephele ♂ from Mr. H. Laitloff, which he writes me was taken some five years since near Greenville, Jersey City. It was so unusual a form that Mr. Laitloff sent it to me for name. At Coalburgh, W. Va., Nephele is never seen, but Alope is the only form; and so on southward.
2.—Alope was described by Fabricius, Ent. Syst., 1793, as fuscous (fusca) with a yellow (flava) band; with two ocelli on fore wings; on hind wing one ocellus above, six below. The band is very broad in the female, usually narrower in the male, pale yellow in both sexes. The ocelli resemble those of Nephele and vary in same manner. Usually they are round, but sometimes oval; are either small or large, often equal, but sometimes the upper is larger, at others the lower. Now and then a third pupilled ocellus appears, and individuals have been taken with but one ocellus (the upper). It is not very unusual to find examples in which a black point, or what may be considered as a rudimentary ocellus, presents itself. On the upper side of hind wing is often a small but complete ocellus near inner angle, but in many cases it is partly or wholly wanting; and occasionally there are one or two black spots in addition. The males in the majority of examples have six small ocelli on the under side of the hind wings; the females rarely have six, and often none at all. At the north, Alope is blackish-brown, more brown in the female; but to the southward brown prevails in both sexes; and it is of a lighter shade, while the under side has a tint of yellow more or less decided over whole surface, often mixed with gray. The band is of yellow, or with a slight ochrey tint. This is a description of the extreme southern type, and to distinguish I call it var. Texana. All examples from Texas which I have seen have a complete anal ocellus, and six ocelli beneath, of pretty large size—larger than in northern Alope—in distinct ochrey rings; the pupils white points with a few blue scales about them in the larger ocelli. Of 70 Nephele ♂ examined, 50 have 6 ocelli, 11 have 5, 3 have 4, 3 have 3, 2 have 1, 1 has 0.
Of 55 Nephele ♀, 6 have 6, 1 has 5, 4 have 4, 13 have 3, 7 have 2, 13 have 1, 11 have 0.
Of 24 Alope ♂, 15 have 6 ocelli, 3 have 5, 4 have 1, 2 have 0.
Of 25 Alope ♀, 12 have 6, 1 has 4, 4 have 2, 4 have 1, 4 have 0.
Therefore of Nephele ♂, 71 per cent. have 6 ocelli, 4 per cent. have under 3; 1.4 per cent. have 0.
Of Nephele ♀, 11 per cent. have 6, 56 per cent. have under 3, 20 per cent. have 0.