It is quite possible, as Mr. Edwards suggests, that the so-called “Vanessa Pluto” may be the ancestor of P. Diana, though in the narrower banding of its wings, with but one row of submarginal spots, it more nearly resembles some of the East Indian forms of Junonia Hedonia: the two genera to which these species belong agree in many respects, and are perhaps nearly allied.
Later, he figures the fossil and refers it doubtfully to Junonia, appending the following remarks:[Z]—
I have noticed this species at p. 109 of my catalogue of Fabrician Diurnal Lepidoptera; Mr. W. H. Edwards of W. Virginia having decided in his Butterflies of N. America that it is unquestionably an Argynnis allied to A. Diana, notwithstanding the important discrepancies which Heer points out [128]. That it may bear some distant relationship to A. Diana is quite possible, but that it is “plainly an Argynnis” is quite another thing; to my mind it is plainly a Vanessid, probably a Junonia near to J. Hedonia, and I think some points in Heer’s description (of which Mr. Edwards takes no notice) are very important, as evidencing its near relationship to J. Hedonia rather than to A. Diana [here he quotes Heer’s description of the submarginal spots].
The ocelli are well shown in Heer’s figure, but in the woodcuts by Lyell and Edwards, which have in other respects been made much darker than the original, the indication of the lower edge of the ocelli has been omitted altogether, and, consequently, the resemblance to the species of Junonia is rendered less evident. I think it just possible, from the great resemblance which V. Attavina of Heer bears to the under surface of J. Hedonia, that it is the reverse of J. Pluto.
This species is very simple in its markings ([Pl. II], fig. 17), the whole upper surface, excepting a broad space next the outer border of the fore wings (the equivalent part of the hind wings is not preserved) being of an uniform dusky tint; a broad belt of a lighter shade margins the (fore) wings, growing less distinct from the darker base above the next to the lowest subcostal nervule; this belt darkens toward the outer border, especially in slight dusky fleckings along the nervures and down the middle of the interspaces; the latter streaks reach small, round, blackish spots about one-quarter the width of the interspaces, in the middle of the basal two-thirds of their lighter parts. Heer represents them too far from the outer margin of the wing, and as often crowned above with a dark semicircular line, which is not at all indicated in the drawing made for me; these spots are found in all the interspaces below the outermost superior subcostal nervule, but they are very indistinct and minute above, faint below and only distinct and as large as stated in the three interspaces next above the lowest median nervule. The light belt is two interspaces wide in the upper median interspace, but widens a little above this and is separated from the darker base by a vague and very slightly crenate line (less crenate than in the representation by Heer), which approaches the outer margin at the nervures and to a slightly greater extent in the lower part of each interspace than in the upper.
Pierids with so dark a coloring as appears in this fossil are not unknown, particularly in the genera Archonias and Pereute; compare for example the figure given in Doubleday and Hewitson’s Genera of Diurnal Lepidoptera, Pl. V, fig. 2. And that markings of this character are not unknown, compare some species of Ixias, Hebomoia and allied genera; if the colors of Hebomoia Leucippe, as given by Doubleday and Hewitson, were reversed, the resemblance to Pluto would be rather close; and while light spots in a dark border are the rule in this subfamily, dark spots on a light ground are not unknown, and the reversal of tints is a not uncommon occurrence in nearly related Lepidoptera.
A second fossil, which I have been unable to see or to have redrawn, is given by Heer as probably representing the under surface of the same insect. His remarks are as follows:[AA]—
Hierher rechne ich auch ein Stück eines Unterflügels aus der Grätzer Sammlung, das bei Taf. XIV, Fig. 5 [[Pl. II], fig. 15], dargestellt ist. Die Hauptadern treten an diesem Flügelstücke alle hervor. Die beiden Mitteladern schliessen ein nicht sehr grosses Mittelfeld ein; ob dieses durch einen Verbindungsast zwischen den beiden Mitteladern geschlossen ist oder nicht, war mir nicht möglich zu ermitteln: bei guter Beleuchtung glaubte ich dort einen schwachen Quereindruck zu sehen, der als Verbindungsast zu deuten wäre; jedenfalls wäre derselbe aber äusserst zart, viel zarter als die übrigen deutlichen Adern. Die äussere Mittelader sendet 4 Aeste aus, der erste entspringt nahe der Flügelbasis und läuft nach dem Aussenrande, die drei folgenden entspringen näher flügelspitzwärts. Die v. interno-media zerspaltet sich in 3 Aeste, ganz so wie die des Oberflügels, welche auch in gleicher Weise verlaufen. Alle 3 Aeste sind fast gleich weit von einander entfernt und entspringen nicht von einem Punkt. Die vena analis zerspaltet sich bald nach ihrem Ursprung in zwei Gabeläste, welche nach aussen laufen. Die Farbe des Flügels ist ein helles Graubraun.
Fig. 1.