It is evident that the object is a cast, for the veins of the wing which lie uppermost on the stone are impressed as we see them on the upper surface of the wings of living Oreades, while those of the wing lying beneath (veins which are plainly covered by the impressed nervures where the two come in contact) are in relief, as seen on the under surface of the same butterflies; that is, we have here the reverse of what would be the case, were we examining a living butterfly in this position.
The parts before us are: a poorly preserved body, vague indications of the terminal palpal joint, an antenna (probably a portion only), an unrolled tongue, the hinder pair of legs and portions of the other pairs, the greater part of the two front wings and fragments of the base of the hind wings. Of the latter, no border remains and only the base of a few of the nervules, which give scarcely any additional information as to the pterology of the insect. The only portion of the margin of the front wings which can be determined with certainty is the most essential part, the apex and the upper half of the outer border of the left wing, enough to show that its general contour was similar to that of the European Satyrids of the present epoch; but throughout the remainder all the nervules can be exactly traced. This being then the best preserved portion of the insect, we will consider its structure in detail, subsequently adding whatever can be gleaned from the examination of the other parts.[Q] [The account of the structural framework of the wing is given under the genus].
The basal two-thirds of the wing appears to have been more darkly clouded than the other portions, although in this fuscous area there is apparently a clearer space towards the upper, outer portion of the cell. There is also a distinct, darker, uniform and equal rounded spot in the middle of the outer two-thirds of the lowest subcostal interspace, nearly reaching the nervule on either side; in the specimen it appears to be broader than long by encroaching upon the next interspace in front, but this is evidently only apparent, the spots of the two wings (one of which I have stated to be a little in advance of the other) being blended. The object is so well preserved that one can see throughout the parallel series of minute punctures forming the points of insertion for the scales, outlines of the latter of which I have failed to discover. The wing is 28·5mm. long, the tip of the cell being distant 15mm. from the base of the wing; the costal nervure is inflated for a distance of 6·5mm., and the extreme width of this portion is 1mm.; the rows of punctures indicating the former insertion of the scales are ·12mm. apart.