PEEVIOUS DESCRIPTIONS AND STUDIES. 23 



same age, three species of diatoms were met, viz: Melosira granulata (Ehr.) Ralfs., 

 Diatoma Tiyemale K. B., Cocconema parvum W. Smith. * * * The most interest- 

 ing discovery, however, was the finding of diatoms in the stoneware clay at Glen 

 Cove. The species are: Melosira granulata (Ehr.) Ralfs. [and] Stephanodiscus 

 niagarse Ehr. * * * " 



In a bed of diatomaceous earth on Lloyd Neck the following diatoms were 

 found (p. 168): 



Melosira granulata (Ehr.) Ralfs. Navicula varians Greg. 



Stephanodiscus niagarse Ehr. Navicula lata Breb. 



Epithemia turgida (Ehr.) Kutz. Eunotia monodon Ehr. 



Eneyonema ventricosum Kutz. Gomphonema capitatum Ehr. 



Cymbella delicatula Kutz. Stauroneis Phoenecenteron Ehr. 



Cymbella cuspidata Kutz. Fragilaria construans Grim. 



Navicula viridis Kutz. Synedra afnnis K. B. 



Navicula cocconeiformis Greg. Campyloneis Grevillei regalis. 



Navicula major Kutz. Triceratium trifoliatum. 



The author does not make it clear, however, whether he regards the bed as Cre- 

 taceous in age, although this is inferred from the text. His final words are (p. 169) : 



In the kaolin found near Kreischerville [Staten Island] were discovered a number of diatoms, which Dr. 

 [D. B.] Ward informs me are either Cocconeis placentula Ehr. or Cocconeis pediculus Ehr. Their occurrence is 

 also of great interest, as these kaolins are known to be middle Cretaceous beyond doubt. 



It seems to me that the results obtained from this hasty examination of the clays are sufficiently encour- 

 aging to warrant a further and detailed search. The correlation of strata by means of their microscopic 

 organisms has been successfully tried elsewhere, and further work might prove it applicable to the clays of 

 Long Island, whose age and stratigraphic relations need much further elucidation. 



The Northport clays were subsequently submitted to a more critical examination 

 by Mr. Ries, and a number of plant remains were found in them. These were sub- 

 mitted to me for study, and among them I was able to identify, provisionally, Pali- 

 urus integrifolius Hollick, Lauras angusta Heer, Proteoides daphnogenoides Heer, 

 Paliurus sp., Myrsine sp., Celastrophyllum sp., and Williamsonia sp. This list, 

 together with Mr. Ries's remarks on the clays, is included in his paper "On the 

 Occurrence of Cretaceous Clays at Northport, Long Island/' in which he says: 



In a previous paper the writer mentioned this clay deposit and expressed the belief that it would be found 

 to be of Cretaceous age. Such has proven to be the c"ase. In a recent visit to the locality a careful examina- 

 tion of the section exposed showed that a brownish-black seam of the clay, two feet thick, contained plant 

 fragments in great quantity, and a few of them were sufficiently well preserved to permit identification and 

 prove the Cretaceous age of the deposit beyond doubt. 



All the facts included in these three papers by Mr. Ries were finally embodied in 

 his " Clays of New York; their Properties and Uses," b together with plates repre- 

 senting some of the exposures and others in which the diatoms and many of the 

 characteristic Cretaceous leaves are depicted. 



In 1894 Mr. Charles L. P.ollard published a brief account of the Elm Point, Long 

 Island, fossil leaf locality, 6 in which are enumerated the following four species: 

 Liriodendron simplex Newb., Diospyros primseva Heer, Magnolia alternans Heer, 

 and Platanus Newberry ana Heer. 



« School of Mines Quart., vol. 15, 1894, pp. 353, 354. 



6 Bull. New York State Mus. No. 35, vol. 7, June, 1900, pp. 595-611. 



c Trans. New York Acad. Sci., vol. 13, 1894, pp. 180, 181. 



