At the anterior upper extremity of the head is a dark prominence which seems to be the terminal joint of a palpus; it extends ·75mm. beyond the head and is of a nearly uniform width (·2mm.), scarcely tapering, with a rounded tip. The basal portion of an antenna, 5mm. long, is slender and apparently begins to increase slightly and very gradually in size, as in the genus Œneis Hübn. A finely impressed line, 7·25mm. long, appears to be the unrolled, though slightly curved tongue.
One of the hind femora projects 2·5mm. beyond the body; its tibia and tarsi are stretched in a single line, at an angle with it, but as the tip of what is apparently the other hind femur strikes them beyond the tip of their own femur, it is impossible to say whether they do not overlap, or are not overlaid by, the tibia and tarsi of the opposite side; their united length on the stone is 5·6mm.; but if both hind pairs are present, their probable length is 4·5mm.. There are also some remnants of the other legs, but in so fragmentary and confused a state that nothing can be determined from them, nor anything surmised of the length or structure of the front pair.
In the illustration of the fore wing given in the Revue et Magazin de Zoologie (fig. B), and copied in the Geological Magazine (fig. 3), the artist neglected to mark the position of the spot upon the wing. This is given in our [Pl. I], fig. 5, which, as well as fig. 2, is taken from the originals of my former plate.
Tertiaries of Aix, Provence, France; Museum of the city of Marseilles.
NYMPHALES—NAJADES—PRÆFECTI.
EUGONIA Hübner.
Fore wings considerably more than half as long again as broad, the costal border scarcely bent at a little distance from the base, beyond that nearly straight to an equal distance from the tip, where it becomes more curved; outer border with the portion above the middle of the lower subcostal interspace very slightly concave, having a general direction at a very little less than a right angle with the central portion of the costal border, beyond suddenly receding at a little more than a right angle to the middle of the subcosto-median interspace, and continuing in a deep crenulate curve to just below the lower median nervure, where a prominent rounded tooth is found, and below which the border is excised, its angle rounded off; inner border very nearly straight, scarcely convex on the basal two-thirds. First superior subcostal nervule emitted a little beyond the middle of the outer two-thirds of the upper margin of the cell; the second a little more than half way from the origin of the first to the tip of the cell; the third midway between the tip of the cell and the origin of the fourth; the latter at three-fifths the distance from the tip of the cell to the apex of the wing; second inferior subcostal nervule arising scarcely one-third way down the cell; the cell considerably less than half as long as the wing, and three times as long as broad; middle of the basal curve of the last median nervule connected with the vein closing the cell.
The butterflies of this genus, which are generally above the average size, strongly resemble those of the genus Polygonia, in the form, color and design of the wings, but on the upper surface of the fore wings the costal markings are much heavier.
The above characters are wholly drawn from recent species of the genus.