SOUTH-WEST COAST OF PURBECK. 369 



coves, which the sea has excavated along this 

 shore ; nine sections of the beds between the chalk 

 and the Portland oolite being exposed, within a 

 distance of five miles. The Wealden, Purbeck, and 

 Portland strata, which on the south-eastern coast 

 form on the south of the chalk downs a tract of 

 country of considerable breadth, are here dimi- 

 nished to one-third of a mile, or even less ; so 

 that in the space of a few hundred yards, the 

 entire series may be examined; for the strata 

 so rapidly converge to the westward, " that the 

 total distance from the top of the greensand 

 to the beginning of the Portland oolite, which 

 is about two miles and a half between Ballard 

 Downs, and Durlstone Head, is but 150 paces in 

 Durdle Cove."* 



The plan of the coast, lign. 31, from the western 

 end of Worbarrow Bay to Whitenore, shows the 

 situation of the bays we are about to examine. 

 The " Sterne's Back" is part of the lofty range of 

 chalk downs, which, interrupted here and there by 

 deep valleys, in one of which the village of West 

 Lulworth is situated, continues westward to Chal- 

 don Downs, forming the inland barrier of the 

 Coves, and the line of cliffs from Bats Corner to 

 Whitenore Point. The scenery in this part of the 



* Dr. Fitton. 



