AND FRESH-WATER FORMATIONS. 325 



tion, for a convenient phraseology ; convenient, as 

 saving the trouble of observation and reasoning, 

 equally. There is some truth also in Breislak's sati- 

 rical remark, that The London clay, The Muschel- 

 calk, and so on, are but modes of national vanity. 



I shall quote the two last described examples, those 

 of Paris and the Isle of Wight, as specimens of 

 actual details, and as examples of differences under 

 analogy, these being also more instructive on this 

 last subject, on account of their proximity. But I 

 must condense, and refer to the well-known original 

 reports ; premising, however, that these are by no 

 means always free of system. 



In the basin of Paris, the lowest strata consist of 

 sand and of clay, with marine remains, followed by a 

 deposit called the Calcaire grossier, including many 

 subordinate strata, and series of strata, as they are 

 considered, consisting of limestone, marl, sandstone, 

 chert, and shale, and containing also marine shells. 

 This is, evidently, a marine deposit, and is called the 

 first marine formation ; but, in the upper parts, it 

 contains fresh water shells, and Lignite. Above this, 

 another series has been constructed out of certain 

 strata of limestone, and of calcareous and argillaceous 

 marl containing gypsum; including also, marine 

 shells and fresh water ones, lignites consisting of the 

 palm tribe, and the bones of quadrupeds and amphi- 

 bious animals. This series has been called the lowest 

 fresh water formation. Still higher, follows marl 

 containing marine shells and remains, sandstone and 

 sand, and a cavernous chert, or the millstone ; form- 

 ing what is called the upper marine formation, though 

 it is a question whether this last rock does not belong 

 to the fourth series. That is a calcareous rock con- 

 taining fresh water shells, of species still existing, 



