3.—The dark Satyrus which inhabits Illinois and westward has gone by the name of _Nephele_, though differing somewhat from _Nephele_ of the east. I was struck by the difference between a series sent me by the late Mr. Walsh from Galena, years ago and when I first began collecting butterflies, and a series of _Nephele_ taken in the Catskills, and I have always kept the two apart in my cases, considering the Illinois form as at least a well marked variety. Mr. Worthington has recently written me: “I have received a lot of _Nephele_ from New Hampshire and am surprised at the difference between them and the Illinois _Nephele_.” The males of this last are almost black, the ocelli are very small and without rings. But in some examples there is a faint russet or yellowish tint about the ocelli, and perhaps on the space between them. On the under side the rings are russet or ochraceous, on both wings. The females are almost invariably and uniformly dark, and only occasionally is there a paler shade over the extra discal area of fore wings. Out of a number of females I find but one in which there is a clouded yellow space about the ocelli, and only three on which there are yellow, though hazy, ocellar rings. Of 16 ♂, 14 have 6 small ocelli beneath, 1 has 5, 1 has 2. Of 19 ♀, 2 have 6, 2 have 5, 6 have 4, 2 have 3, 6 have 2, 1 has 1. This form prevails exclusively to the Rocky Mountains. I have received it from Nebraska, Montana, Colorado and New Mexico, but _Alope_ is unknown to me from that region. In CAN. ENT., ix., 141, 1877, I gave the history of _Nephele_, bred from eggs laid by a typical female from the Catskill Mountains, Hunter, N. Y. In fall of 1878, I wrote to several correspondents for eggs, and by their good will obtained many. Prof. Lintner and Dr. Bailey sent eggs of _Alope_ from Albany, N. Y. Rev. Mr. Hulst, with the zeal and kindness which distinguishes him, crossed the rivers from Brooklyn to Hoboken, and brought away females of _Alope_, from which he obtained eggs for me. I got _Alope_ eggs here at Coalburgh from three females. A friend at Hunter sent eggs of _Nephele_, and Mr. Worthington sent many of the Illinois form from Chicago. In each case the parent was sent with the eggs that the type might be noted. From Albany, Hoboken is 150 miles south; Coalburgh 800 miles southwest; Hunter is 35 miles southwest of Albany and of about 2,000 feet greater elevation. Chicago is about 800 miles northwest of Coalburgh and 1,000 west of Albany. So that the five localities are separated by considerable distances, and there has probably been no intercommunication at any time so far as these insects are concerned.