With Lethe (Pl. II, fig. 6) and Debis (Pl. II. fig. 10) the fossil genus can better be compared, as far as the form of the wing, the dilated costal vein, and the position and direction of the straight vein closing the cell are concerned; but in both these genera only a single superior subcostal nervule is emitted before the apex of the cell; the form of the cell again shows rather closer affinity between Lethites and these genera, although the difference in these respects is but slight. It is by no means distantly related to Enodia, in which two subcostal nervules are emitted before the tip of the cell, but differs from it in the much greater and more abrupt swelling of the costal vein, and in the much greater distance beyond the second divarication of the median nervure at which the vein closing the cell meets this nervure. It even exhibits no small affinity to Cercyonis, and especially to those species in which there is little dilation of the median nervure; the costal nervure is swollen in precisely the same way, and the superior nervules of the subcostal nervure are much the same; but the form of the wing is strikingly different, and the lowest subcostal interspace much wider at the base, in comparison with the width of the base of the subcosto-median interspace, in Cercyonis than in Lethites; and this seems to be a character of considerable importance. It may be noted in this connection that the markings of the fossil must have closely resembled _Cercyonis Pegala_. Its nearest ally among living European types would seem to be _Maniola Hermione_, in which the costal and median veins are about equally swollen. The neuration of Lethites agrees with this genus in much the same way as it does with Cercyonis, the comparative width of the interspaces beyond the cell being very different in the living genera from what it is in the fossil. In the form of the wing Maniola agrees much better with Lethites than Cercyonis does, but the costa is much more arched, and the cell is much the longer in Maniola; were there no obscure spot in the lower median interspace in the male of _M. Hermione_, the markings of the fossil would agree with it almost perfectly. LETHITES REYNESII SCUDDER. Plate I, figs. 2, 5. _Satyrites Reynesii_ SCUDD., Rev. et. Mag. de Zool., 1871-72, 66-72, pl. vii (1872); IB., Descr. Pap. Foss. 1-7, pl. (1872); IB., Geol. Mag. ix, 532-33, pl. xiii, figs. 2, 3 (1872); IB., Descr. Foss. Butt. 1-2, pl., figs. 2, 3 (1872); BROD., Distr. Corr. Foss. Ins. [_Satyrites Reynesii_], 8-9 (1873). I give below the original of the first paper cited above, excepting the portion which was quoted under the genus.