DURDLE, OR BARN-DOOR COVE. 385 



Lulworth Cove, in the highly inclined strata of 

 the cliff, that a considerable number of petrified 

 trunks of trees are exposed. Some are entirely laid 

 bare by the washing of the sea, and others partly 

 so ; but several are almost wholly encased by con- 

 cretions of soft burr-stone, and have their roots 

 fixed in a layer of black earth (termed dirt-bed 

 by the quarrymen) ; in precisely the same relative 

 position, and interspersed with similar rounded 

 fragments of limestone, as in the fossil forest of 

 the Isle of Portland, hereafter noticed. 



The lowermost strata are the Portland oolitic 

 limestones, full of marine shells ; on them is 

 superimposed the layer termed the " dirt-bed,'" 

 with the fossil trees. This is covered by cream- 

 coloured calcareous stone disposed in very thin 

 undulated laminae, and locally termed "soft burr ;" 

 and above are shales, and thin bands of limestone, 

 belonging to the lowermost beds of the Purbeck. 



There are also layers of chert containing chal- 

 cedonic casts of freshwater shells, in the cliff just 

 above the sea level.* 



Durdle, or Barn-door Cove. — There are 

 several smaller bays, which are worth examining 



* On the hills near Lulworth, there are detached hlocks of the Hertfordshire 

 siliceous pudding-stone, lying upon the clialk ; and large masses of this con- 

 glomerate may be seen in the street of West Lulworth, and in the walls of 

 some of the cottages. 



