The fossil to which I have given this name is exceedingly obscure, having no color whatever distinct from the stone in which it is imbedded; this is of a chalky gray color. I have seen both impression and reverse, the latter a little in relief. The fossil consists of both anterior wings, one beneath and slightly in advance of the other, thus complicating very greatly the study of the already indistinct neuration; in addition to this the wings are crumpled and additional longitudinal lines are present, scarcely distinguishable from the longitudinal nervures. On this account it should be stated that there may be some doubt about the exact position of the lowest three branchlets of the subcostal nervure. The stone has been broken next the edge of the wing, and its form can thus be traced where the real border is wanting, although again the drawing presented may be slightly inaccurate next the inner margin; but the probabilities are great that it is correct throughout. The spots which are represented on our plate in the middle of the lower median, subcosto-median and lower subcostal interspaces, are only irregularities of surface on the stone, but as they appear in regular position are not improbably dark spots, upon a light ground. A few points for the insertion of the scales can be detected near the apex of the wings, ·075mm. apart. The neuration of the fossil agrees better with that of _Delias Pasithoe_ than with that of any other butterfly I have examined. Length of wing, 21mm.; greatest breadth, 9mm.. Tertiaries of Aix, Provence, France. Collection of Count de Saporta. PAPILIONIDÆ—DANAI—VORACIA. PONTIA FABRICIUS. _Pierites_ HEER, Insekt. Tert. Œning., ii, 182; IB., Nouv. Mem. Soc. Helv., xi, 182; GIEB., Faun. der Vorw., ii, 187. Fore wings fully three-quarters as long again as broad, the costal margin slightly convex at the basal and apical fifth, scarcely bent at an angle with the nearly straight middle portion, the outer angle abrupt but softened. Outer margin nearly straight and inclined at an angle of forty-five degrees with the middle portion of the costal border, above the middle subcostal nervule receding slightly in a gentle curve. Inner margin straight, the outer angle well rounded. Costal nervure terminating a little beyond the middle of the margin. Subcostal nervure with three superior branches; the first arising shortly before the middle of the outer half of the cell, a little nearer the apex of the cell in the female than in the male; the second arising scarcely (male), or a very little (female), beyond the tip of the cell; the third emitted at about two-fifths the distance from the apex of the cell to the outer margin, forked at the extreme tip in the male. Cell half as long as the wing and nearly four times as long as broad.