Perhaps more than any other equal area in America, Long Island has been the subject of indecisive geologic study and lively disputation. For over a century it has afforded the students of stratigraphie and surficial geology an opportunity for difficult diagnosis, and the complex features have been attacked from every position of geologic philosophy. But the problem has outrun the investigation. The preglacial deposits are thought to have been overridden, disturbed, and confused by the recurrent ice-sheets, and much remains to be determined with reference to correlation of strata, the origin of the island, the amount of Pleistocene movement, and the genesis of the topography.
The most conspicuous topographic features of the island, which have naturally received most attention, are the belts of morainic hills. But quite as interesting and of equal significance are the extensive sandplains, equivocal in their origin. The present paper will present the facts which prove . . .