CLAYS OF NEW YORK 609 



The above may very possibly be some of the Cretaceous clay 

 overlain by the yellow gravel. Borings made at various points 

 along the shore of Arthur's kill, between Kreischer's factory and 

 Wood & Keenan's brick yard, penetrated a blue clay at a depth 

 of 3 or 4 feet. This latter is no doubt of very recent origin. 



At the Anderson brick co.'s pit near Greenridge, the lower 

 clay, which is of a black color, shows signs of disturbance, 

 and slickensided surfaces are common. The upper portions of 

 the bank are of blue and gray colors, and at one spot there is a 

 thick seam of lignite. The clay is not sufficiently refractory for 

 fire brick. Fragmentary plant remains were found by the writer 

 in this pit, but they are not nearly so perfect as those found in 

 the fire clay pit at Kreischerville, and which have been figured 

 and described in minute detail by Dr Arthur HoUick of Columbia 

 university. 



Spicules have been observed in the fire clay at Kreischerville, 

 Staten Island. In the kaolin found near Kreischerville were dis- 

 covered a number of diatoms, which Dr Ward informs me are 

 either Cocconeis placentula Ehr., or Cocconeis 

 Pediculis Ehr. Their occurrence is also of great interest, 

 as these kaolins are known to be middle Cretaceous beyond doubt. 



Stony glacial clays occur also underlying the flats at Green 

 ridge, Staten Island. 



One mile and a quarter northeast of Kreischer's fire brick fac- 

 tory an excavation has been made for obtaining a micaceous kaolin. 

 About 15 feet of it is exposed. A quarter of a mile north of this 

 locality is the pit of the Staten Island kaolin co. The kaolin is evi- 

 dently a continuation of that exposed in Kreischer's pit, but is ap- 

 parently not as thick. The deposit has suffered disturbance by the 

 ice sheet and the layers are intermixed with the till. At the north- 

 east side of the excavation a bluish sandy clay containing frag- 

 ments of lignite is found to underlie the kaolin. 



In the spring of 1898 Kreischer Bros, opened a new pit just 



