610 CLAY, MARLE, AND SAND. 



B. Bituminous marie : more or less distinctly 

 schistose. 



There is considerable obscurity in the history 

 of this substance ; as it contains fish, and is yet 

 said to accompany primary limestone, as above 

 remarked. It is found in various parts of the 

 continent of Europe. 



The other substances known to agriculturists 

 by the name of marie, belong to the alluvia, 

 where they are fully described. 



SAND. 



A. Quartz alone. 



B. Quartz and clay. 



C. Quartz and limestone, or quartz, limestone, 

 and clay. 



D. Quartz and mica 



These occur in different parts of the series of 

 the secondary strata : some of them, conspicu- 

 ously, under the English chalk. They are some- 

 times partially indurated into sandstones, as 

 already mentioned. 



E. Quartz and highly ferruginous clay, or ochre, 



