In regard to the Pacific side of this Talamanca section, Professor H. Pittier says, “The southern coast Cordillera, as a whole, is formed of a nucleus of basaltic or syenitic rocks, above which are found successively limestone in very deep banks and sometimes fossiliferous: then argillaceous and marly schists; again, sandstone and conglomerates, the latter forming generally the crests of the hills and giving way very easily to atmospheric action, which produces its decomposition and is the cause of sterile lands characterized by savannas and the absence of forests on the upper parts of the mountains, as well as in certain lower and denuded parts. The conglomerates are made up of heterogeneous elements whose resistance to erosion is variable. Some disintegrate as soon as they are exposed to erosion, while others remain unaltered for a long time. For this reason the savannas are in many places covered with stones of varied sizes.” The lower valley of the Pirris presents a cap of impervious red clay, and, as the waters do not readily drain off they become stagnant and make an unhealthy district. Dr. Frantzius, referring to the same region, speaks of diorites and syenites, also of calcareous deposits of the Miocene age covered with sandstone formations containing useful lignites. In his opinion the mountain of Dota is formed almost entirely of dioritic rocks with some syenitic nucleus. The same scientist says further that the high plains of Caños Gordas are formed of conglomerates of ashes ejected by the volcano of Chiriqui and brought there by the trade-winds which prevail in Central America. The Pacific slope, which comes boldly to the water’s edge, is margined almost throughout by headlands and lofty hills, and has fewer evidences of extensive denudations and erosions than the Atlantic coast. There is also a notable difference between the outlines of the two coasts. The eastern is regular and slightly concave to the southwest, while the western is indented with large and small bays and gulfs. The most northern of these bays is the Salinas, belonging partly to Nicaragua and partly to Costa Rica. It is a spacious deep-water harbor, overlooked by the volcanic peak of Orosi. It is separated from the adjoining bay, the Santa Elena, by Sacate Point.