MODE III. LIMB3TONE. 455 



Cambridgeshire, being, it is believed, an unique 

 example. 



Echinites singularly abound in the chalk-pits of 

 England, with cockles, &c. ; but they are easily 

 separated, and of course foreign to the present 

 purpose. 



Limestone, with ammonites, from Dorsetshire. 



With belemnites, Thuringia. They may per- 

 haps have been mistaken for bones. 



With orthoceratites, Erfurt. 



With nautilites, Upper Austria. 



With strombites, Jena. 



With cochlites, Norway. 



With chamites, Mont Martre. 



With gryphites, Alsace. 



Numerous other examples might be added, 

 i 



STRUCTURE IV. ZOOPHYTIC. 



Zoophytes, including the mollusks, also abound 

 in common limestone. They are of many varie- 

 ties; as the turbinated, the porpite, the fungite, 

 the astroite, &c. Among them may also be 

 classed the milleporite, the celleporite, the entro- 

 chite, either in many or single joints, and of several 

 varieties, the gorgonite, the coralite, and the en- 

 crinite. The trochite is a word used by some for 

 single joints of the entrochite, which can scarcely 



