Of the many volumes on the archeologic problems of Easter Island, only two1 deal with the geology even in a fragmentary manner. Other brief discussions are incomplete. Verlain2 made the first attempt to describe the geology of the island, but his information was obtained from specimens deposited in France and his paper consists mostly of petrological descriptions. Skottsberg 3 described the general geology and physiography, after an examination in 1917. Chubb4 visited the island in 1924 and has published the most comprehensive treatise on the geology and petrology. In addition, brief references are made to the petrology of the island by Rosenbusch,5 Tilley,6 Speight,7 and Lacroix;8 of these, the papers by Rosenbusch and Lacroix seem to contain errors which merit correction.
In the latter part of 1933, the writer devoted eight days to a study of the geology of the island and the collection of a large suite of . . .