CLAYS OF NEW YOKK 597 



of Hempstead harbor. Carpenter's clay resembles that of Cretace- 

 ous age found on Staten Island, but its age has yet to be proven. 

 The sandstone fragments found in the clay across the inlet are found 

 along the shore of it to Carpenter's clay bank, but none are found 

 in it. Dr, Merrill has found plant remains in this clay, but they 

 were not sufficiently well preserved for identification. (^8ee paper 

 previously cited.) A microscopic examination of the clay revealed 

 the presence of the following diatoms; all freshwater forms: 



M e 1 o s i r a g r a n u 1 a t a (Ehr.) Ealfs 



S t e p h a n o d i s c u s N i a g a r a e (Ehr.) 



D i a t m a h y e m a 1 e ( ?) K. B. 



A deposit of gTay sandy clay 30' feet thick was uncovered on the 

 north of Mosquito inlet in the spring, of 1898, on the property 

 of Mrs Helen McKenzie, but it is distinctly different in its char- 

 acter from that on the south side of the inlet. 



On Center island in Oyster bay we find the most western of 

 a series of clay beds which bear a great similarity to each other. 

 The others are on AYest neck, at Freshpond and on Fisher's island. 

 The clay on Center island consists of two kinds, a lower bluish 

 clay and an upper brown sandy clay. Overlying this latter is a. 

 stratified sand. The layers of clay undulate in several direc- 

 tions. Dr Merrill mentions the occurrence, 1 mile north of 

 this clay pit, of a bed of white fire clay at a depth of 25 feet 

 under the drift and sand. The only organism thus far met ir. 

 this clay is one species of diatom, viz, Stephanodiscus 

 ]Sr i a g a r a e (Ehr.), and a curious spiny hair. 



At Jones's brick yard on the east shore of Coldspring harbor 

 is a thick deposit of clay. The lower portion is tough and con- 

 tains little sand. The upper portion is much more sandy and of 

 a brown color. The clay bank is over 100 feet in hight, the layers 

 having been folded under the pressure of the advancing ice sheet. 

 A layer of diatomaceous clay occurs in the upper portion of the clay 

 bank; its position is shown in the following section given by Dr. 

 Merrill.^ 



1 Ann. N. Y. acad. sci. 1884. 



