231 



CONCRETIONARY CELLULAR LIMESTONE 

 OF DURHAM. 



G. ABBOTT. M.R.C.S., F.G.S., 



Tmibridre J J 'ells. 



It would be no easy task to decide which is the most puzzling- 

 of all the sedimentary rocks in the United Kingdom — at any 

 rate to satisfy many geologists as to whether this or that had 

 such a distinction. I venture, however, to put forward the 

 cellular limestone, and do so without any hesitation. It has 

 long- been and still is a complete mystery as to how it was 

 formed, and also from what kind of bed so large an amount of 



Magncsian Lim-stonc . ■ ..v/eil. 



magnesia was derived. Geolog-ists in the neighbourhood of 

 Sunderland, and others also who have known it for many years, 

 iire unanimous as to this. They are also agreed as to the 

 wonderful structure which it exhibits being- entirely due to 

 •causes which are not associated with either animal or vegetable 

 life. 



The days of Eozoon are, I suppose, past and gone. We 

 hear little of it now perhaps because it is no longer considered 

 to be a fossil. Yet in resemblance to foraminifera, corals, etc., 

 the cellular limestone is very much more astonishing and ought 

 to be more widely known. Those w^ho go to see these beds are 



1905 August I. 



