PROOFS OF SUBMERGENCE 297 



why this difference? A similar difference is found in the eastern rem- 

 nants of the later moraine, the limitation being the marine plane shown 

 in the map. Fuller seems to have had some doubt as to the nature of 

 these wave- washed moraines. He called them^, with some misgiving, 

 "depressed moraines'' and defnied them as follows: 



"In brief, the term is applied to irregular marginal accumulations devel- 

 oped along the ice-front in line with the normal morainal ridges, but failing 

 to rise above the adjacent outwash. The 'depression' is due rather to the non- 

 accumulation of morainal material than to an excess of outwash" (pages 33- 

 34). 



The Shinnecock and Montauk masses have no deficiency of material. 

 They simply have lower altitude, and partial submergence of the mo- 

 raines is the perfect explanation. 



East of the meridian of Manorville the later moraine was mostly sub- 

 merged or has been cut away by wave erosion. The submerged, sandy 

 moraines Fuller calls "pseudomoraines" (page 35). He says that they 

 are largely dune sand, although having morainal topography. The char- 

 acters and genesis are probahly similar to those of the Shinnecock Hills. 



KETTLE PLAINS 



Another peculiar feature, closely related to the subdued moraines and 

 equal proof of the submergence of the island, is the occurrence of many 

 kettles far out on the plain beyond the moraines. The kettles of the 

 island have been admirably described by Fuller (27, pages 38-44), but 

 the significance of those in the plains has not been recognized. 



Kettles occur profusely in the moraines, which is where they specially 

 belong, and may occur wherever the stagnant ice-margin has lingered. 

 No kettles occur on Long Island in the outwash plain and none in the 

 submerged plain facing the sea until we pass east to Shinnecock. A 

 single exception is the small basin northwest of Babylon, of uncertain 

 origin. 



Kettle plains are found at Southampton and Bridgehampton and east- 

 ward, in connection with or facing the earlier moraine, and through the 

 low area between the two moraines east of Yaphank and Eocky Point. 

 Riverhead and Mattituck lie in a district rich in kettles. Some portions 

 of the kettled areas are as flat and smooth as any parts of the island. 

 The village of Bridgehampton is surrounded by kettles, which occur 

 within one and one-fourth miles of the ocean beach and three miles be- 

 yond the rough moraine. And this is a level district, with much loamy 

 surface soil. 



