undoubtedly existed when the lignitiferous beds were accumulating, I conceive it is not improbable that the climate, during the lignitiferous period, varied on different parts of the coast in a somewhat similar manner as it now does. Looking to an earlier epoch, when the strata of the Cordillera were depositing, there were islands which even in the latitude of Northern Chile, where now all is irreclaimably desert, supported large coniferous forests. TABLE 4. Column 1. Genera, with living and tertiary species on the west coast of South America. (M. d’Orbigny states that the genus Natica is not found on the coast of Chile; but Mr. Cuming found it at Valparaiso. Scalaria was found at Valparaiso; Arca, at Iquique, in latitude 20, by Mr. Cuming; Arca, also, was found by Captain King, at Juan Fernandez, in latitude 33 degrees 30′S.) Column 2. Latitudes, in which found fossil on the coasts of Chile and Peru. (In degrees and minutes.) Column 3. Southernmost latitude, in which found living on the west coast of South America. (In degrees and minutes.) Bulla : 30 to 43 30 : 12 near Lima. Cassis : 34 : 1 37. Pyrula : 34 (and 36 30 at Concepcion) : 5 Payta. Fusus : 30 and 43 30 : 23 Mexillones; reappears at the St. of Magellan. Pleurotoma : 34 to 43 30 : 2 18 St. Elena. Terebra : 34 : 5 Payta. Sigaretus : 34 to 44 30 : 12 Lima. Anomia : 30 : 7 48. Perna : 30 : 1 23 Xixappa. Cardium : 30 to 34 (and 36 30 at Concepcion) : 5 Payta. Artemis : 30 : 5 Payta. Voluta : 34 to 44 30 : Mr. Cuming does not know of any species living on the west coast, between the equator and latitude 43 south; from this latitude a species is found as far south as Tierra del Fuego.