OF CREATION. 21 7 



imperfectly hardened, and form a basis for the great 

 deposit of limestone about to be super-imposed. As 

 we know, from the position of the lias with respect 

 to the underlying red sandstone, that land probably 

 extended not only to the west of England, and 

 therefore into the present Atlantic Ocean, but also in 

 various parts of modern Europe, we may understand 

 that there may have been many islands in the inter- 

 mediate sea, even if the depression in one part was 

 not accompanied by corresponding elevation in an- 

 other. 



However this may have been, the lias sea-bottom 

 was succeeded, as we have said, first by a sandy, and 

 then by a calcareous bottom, and the inhabitants 

 were modified accordingly. Soon a deposit of nearly 

 pure carbonate of lime was formed under circum- 

 stances which allowed it to collect round minute 

 organic particles, and form the peculiar stone we 

 designate oolite ; and this deposit was repeated, not 

 incessantly but at intervals, during the whole of the 

 rest of the period of the marine deposits. The con- 

 ditions being favourable for the existence of such 

 animals as shell-fish, these were developed abundantly, 

 and for a long time their dead and broken shells 

 accumulated, forming at length complete and thick 

 bands of shelly matter, which afterwards hardening 

 became shelly limestone. The seas at this time 

 abounded with fish, amongst which were many 

 species adapted to feed on mollusca, crabs, and lob- 

 sters, most of them being of small size, but provided 

 with solid plates of enamel on the palate, enabling 

 them to crush the hard shells of the animals on which 

 they fed. In the older beds little coral appeared, and 



