136 



beautiful of the Bacillaria. Navìcula major F. T. K. is also present in 

 ali of the three Neocenes periods but it is scarce whilst Actinocychis 

 ralfsii is common. 



Let us trace the periods down from the Upper Neocene or the 

 present living or Recent period. Just as we have the Lower Neocene 

 period which is found no further north on the Atlantic side of the 

 Continent of North America than at Auvergne, Rockaway, Long 

 Island, New York. It goes south into the Gulf of Mexico at Fampa, 

 Florida. Above this comes the Middle Neocene. 



This is from Boston to the Rice Fields of Georgia, the Lower 

 Neocene is mostly nearly white in color and is represented by the 

 celebrated Richmond, Virginia deposit of « infusoria » which is world 

 known. The Middle Neocene is a grey or blue clay. Then comes the 

 Upper Neocene which is distinctly fresh water and is white, grey or 

 black when seen. It comes into commerce as the « infusorial earths » 

 and the « Electro silicon » and various other names which have been 

 applied to it. It is the base of the common tooth powders and po- 

 lishing material and makes the dynamite and explosive material which 

 is so common ali over the world. 



Below the Neocene is the Newark as it is now called. This was 

 known as the Triassic but it is not the typical Triassic of Germany 

 on this Coast it does not seem to be that. In this 1 have seen Ba- 

 cillaria but they must be just referred at present. 



Bacillaria are found in the clay of the Glacial period when ice 

 covered the land down almost to te junction of the Hudson river 

 with the Mississippi in Missouri, forming the edge of the glacier as 

 it is known in North America. This carne down in New Jersey al- 

 most to the mouth of the Rasitan river. In the glaciers now exi- 

 sting in the north the Bacillaria, which are fresh water of course, 

 for the glacier is formed of the ice in that region, are living and 

 are marked as being very small and very scarce. Navicula major 

 F. T. K. and Hant^schia amphioxys A. G. is also present in the snow 

 that falls now and it seems to be one of the first forms of Bacil- 

 laria which is evolutionized. It is common the world over and was 

 first known as one of the Bacillaria Ehrenberg saw and described 

 as Eunotia amphioxys. It is also a Ni/Ischia and now a Ni/Ischia 

 sigmoidea P. A. C. N. It is seen in his Beitrag zur Infusorienkunde 



