Porte d'Enfer it is com- /18 posed of a heavy bed of brain- coral agglomerate, lying upon a grayish or yellowish green calcareous sand-rock. The sand-rock is exposed for a- [illegible] ten feet above sea level, is free from the large masses of which characterizing the upper bed coral and has been much black- ened by the action of the seawater. There is no apparent discordancy between the sand rock and the overlying agglomerate. The strike of the beds is about 2[illegible] N. 30° E. and the dip 10° or 12° toward the N.N.W. Near the sea the surface of the rocks, where nearly horizontal, is roughly er- oded, as at Le Moncel and the Porte d'Enfer. The