1892. | NEW YORK ACADEMY OF SCIENCES. 45 
in 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 Long Island, read before theN Y. 
Acad.Sci., in Nov. 1884, Dr. Merrill describes in detail the forma- 
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 by Dr. 
Merrill. 
On Elm Point is a bed of stoneware clay over 30 feet thick 
and covered with 15 to 20 feet 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 preservation. 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 clay, 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 west shore 
of Hempstead Harbor. Farther up the harbor at Glenwood 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. 
