96 Professor E. Forbes on the Oolite in Ski/e. 



of the shales above the columnar trap, thus brought into 

 contact with the force of the sea ; and as the westernmost 

 extremity of the range of amygdaloidal hills corresponds 

 nearly to the centre of the bay, the ruin of the superincum- 

 bent trap is here very great indeed. It was on the shores 

 of this bay that Sir Roderick Murchison and Professor 

 Sedgwick found the blocks of freshwater or estuary limestone 

 referred by them conditionally to the Wealden. 



On landing, I found similar blocks with similar fossils, 

 but could not see them in situ in the section along the coast. 

 I found, however, very soon, that the black shales included 

 in and underlying the amygdaloidal trap were fossiliferous, 

 and before long had the pleasure to find numerous specimens 

 of Ammonites cordatus and Belemnites Owenii and Beaumon- 

 tianus, indicating the age of these shales beyond a question 

 to be that of the Oxford clay, to which stratum indeed 

 mineralogically they have the most marked resemblance. 



When the tide receded, the beds of shale were exposed in 

 regular sequence along the shore, and beneath them in con- 

 formable succession I found in situ the strata of yellowish 

 crumbly limestone and shale with estuary fossils from whence 

 the blocks referred to had been derived. 



The series of beds seen in the section in descending order 

 is as follows : — 



1. Immediately below the amygdaloidal trap, which is 

 crumbly and wackaceous at the junction, there is a thin band 

 of small rolled pebbles mingled with fragments of jet. 



2. Crumbling blue shales with Belemnites Owenii, 

 Ammonites cordatus, and A. Eugenii, about five feet in thick- 

 ness. 



3. A thin band of concretionary limestone. 



4. Five feet of blue shale with Ammonites and large 

 Belemnites. 



5. Two bands of hard grey concretionary limestone, 

 weathering yellow, in which I could find no fossils, three feet. 



6. Dark blue shales with small Belemnites, seven feet. 



7. Concretionary reddish and yellowish limestone with 

 large Belemnites, one foot. 



8. Blue shales, one foot. 



