1892.] NEW YORK ACADEMY OF SCIENCES. 45 



iu a belt through the centre, so that in describing' them I have 

 gone east along the shore and come back through the centre of 

 the Island. 



In a paper on the Geology of Lonpj Island, read before theN Y. 

 Acad. Sci., in Nov. 1884, Dr. Merrill describes in detail the forina- 

 tions exposed on the island, and mentions the insufficiency of 

 data necessary to afford definite conclusions concerning the se- 

 quence of geological events. Examination of the various clay- 

 outcrops of Long Island during the past season showed that 

 eight years had made some changes, permitting the collection of 

 additional data and obliterating many localities described bv Dr. 

 Merrill. 



On Elm Point is a bed of stoneware clay over 30 feet thick 

 and covered with 15 to 20 ieet of yellow gravel and drift. The 

 gravel has sandstone concretions similar to those found on 

 Staten Island, but none were found containing fossils. The 

 clay is of a dark gray color and contains streaks of lignite in a 

 good state of j^reservation. Leaves are said to have been found 

 in this clay. It is no doubt of Cretaceous age. 



There is an extensive outcrop of clay at Glen Cove, on the 

 east shore of Hempstead Harbor. This has long been known 

 to be Cretaceous, as proven by its contained plant remains, 

 which are in concretions in the clay. The layers of the latter 

 are blue and red. They are considerably tilted. Near this lo- 

 cality and on the shore of Mosquito Inlet is an outcroft of a 

 pinkish claj^ used for fire-brick and stoneware. Dipping under 

 it in a northerly direction is a bed of alternating layers of 

 quartz pebbles and clay. Associated with this is a bed of kao- 

 lin, but the exact relations of the two deposits are not known. 

 Kaolin also crops out from under the gravels on the Avest shore 

 of Hempstead Harbor. Farther up the harbor at Gleuwood we 

 find a yellowish brown clay underneath the yellow gravel. 



Ferruginous sandstone concretions were found at a number 

 of localities in the sands and gravels overlying the clays, but no 

 fossils were found in them. 



Silicified corals were discovered in the sands associated with 

 the yellow gravel on the shore of Cold Spring Harbor. 



There is a deposit of fire and pottery clay at Northport. It 

 is of white, blue and red color and is stratified. The layers are 

 separated by thin sheets of sand. The owner claims to have 

 frequently dug up leaves. This is probably another Cretaceous 

 outcrop. 



The other clays along the north shore have a certain amount 

 of similarity and are considered by Merrill to be of probable 

 Tertiary age. 



