84Mr.De la Beche on the Geographical Distribution of Organic 



General View of the OoliticSeries in Somersetshire and Wiltshire. 



It would be quite out of place to present a general view of 

 this part of our island, as the labours of Smith and Conybeare 

 are well known, and as the rocks in question constitute the 

 type of the oolitic series generally, if we except the Portland 

 beds. 



It may be remarked that the Bath oolite does not occur on 

 the coast of Dorsetshire. A series of clays with limestone, re- 

 sembling forest marble and cornbrash largely developed, there 

 separate the inferior oolite from the Oxford clay. 



The coral rag, as is often the case, is also wanting on the 

 same coast ; that is to say, the beds containing such an abun- 

 dance of corals, whence the name, do not occur, though an 

 equivalent to the Oxford oolite does. 



General View of the Oolite Rocks of Normandy [according to 

 De Catimont)*. 



1. Argile de Honfleur (Kimmeridge clay). Glos sandstones, 



considered subordinate. 



2. Calcaire de Blangy. 



3. Coral Rag, consisting of a series of beds containing many 



oolites 

 * In my paper " On the coasts of Fiance, and of the inland country ad- 

 joining; between Fecamp to St. Vaast:" inserted in the 1st volume of the 

 Geological Transactions, New Series, and written from observations made in 

 the spring of 1821, deceived by the mineralogical resemblance of this lime- 

 stone, as developed at Hennequeville cliff, to some of the Portland stone, 

 I attributed the Calcaire de Blangy to that rock : but 1 now perfectly agree 

 with the French geologists, that the Honfleur and Havre clay is equivalent 

 to the Kimmeridge. Subsequent examinations have shown me that this is 

 very probable ; consequently it was an error to refer the limestones in ques- 

 tion to the Portland stone. 



The following section, by M.deCaumont, of Hennequeville cliff, shows 

 the superposition of the Kimmeridge (Honfleur) clay, the Calcairede Blangy, 

 and the coral rag. 



1. Chalk with gray flints, and numerous alcyonia about 100 feet. 



2. Green earth 40 



3. Argile de Honfleur 60 



4. The same, alternating with many beds of ferruginous sand- ? cyn 



stone full of quartz grains and globules of oolitic iron . J 



5. The same, alternating with many beds of more compact"! 



sandstone, and full of broken shells forming a kind of > 10 

 lumachella J 



6. Sandstone more siliceous than the preceding, containing } ^ 



fewer shells 5 



7. Siliceous limestone, very hard, containing globules of > , 



oolitic iron S 



8. Whitish and slaty siliceous limestone 3 



9. Limestone resembling No. 7 ^h 



10. The same, full of the interior casts of trigonias li 



11. Many beds more or less hard, resembling the preceding ... 3 



12. Bed 



