424 inferior oolite op the bath-dottltltstg district. [Nov. 1907. 



Appendix I. — On the Correlation" of the Bath-Doulting Strata 

 with those of Dorset. By S. S. Buckman, F.G.S. 



Mr. Eichardson has asked me to say a few words about the 

 correlation of the strata described by him with the Upper Inferior 

 Oolite + the Fullers '-Earth rocks of Dorset. As I have had the 

 opportunity of reading his careful exposition in manuscript, I very 

 gladly accede to his wish. 



To make the subject clear I append the following Table (V, 

 p. 425), giving the generalized sequence of ihe strata in North and 

 South Dorset and correlating therewith the Bath-Doulting strata. 



About this Table I would make the following remarks : — There 

 are three horizons which can be correlated without much difficulty, 

 namely : (1) The Fullers'-Earth Hock of Dorset and the Fullers' 

 Earth of Midford ; (2) Beds with stout- whorled Parkinsonia of 

 South Dorset and the Anabacia-luiwesto-nes of Bath-Doulting ; 

 (3) The Building- Stone of Sherborne and the Upper Trigonia-Grit 

 of the Cotteswolds, which Mr. Richardson has followed into the 

 Bath-Doulting district. 



|As to other strata, the Lower Fullers' Earth and the Fusca- 

 Beds of North Dorset are, I fancy, entirely unrepresented in the 

 Bath-Doulting district, where, too, there is but a trace of the 

 strata of the zigzag hemera ; so that in this North Somerset district, 

 as I interpret it, the strata of subcontracti hemera rest non- 

 sequentially in most cases on strata of pie-zigzag date. 



These strata are what Mr. Eichardson has called the Anabacia- 

 Limestones. There is little to represent them in North Dorset; 

 but in South Dorset there are some feet of limestone earlier than 

 zigzag and later than Truellii, characterized by certain stout-whorled 

 Parkinsonian of the type of P. Schloenbachi, Schlippe. Specimens of 

 such stout-whorled Parkinsonian I have found from the Cotteswold 

 Hills to the Dorset coast — for instance, in Gloucestershire in the 

 Clypeus-Giit of Sherborne, near North Leach ; in North Somerset, 

 at Bed Post near Eadstock, and in a quarry about half a mile south 

 of Doulting ; in South Somerset, from the ' upper beds ' of 

 Haselbury near Crewkerne ; in Dorset, from what is known as the 

 ' 2nd bed ' at Burton Bradstock, and its equivalents at Yetney 

 Cross and Chideock-Quarry Hill, near Bridport. It may be assumed 

 that these beds are all contemporaneous ; that the North-Somerset 

 finds, which were not in situ, were really from the Anabacia- 

 Limestones ; and that therefore strata of -post-Tj^uellii date can be 

 traced for a considerable distance. The Doulting Freestone is to be 

 dated as Truellii hemera ; and a slightly-earlier date in the same 

 hemera must be given to the Upper Coral-Bed (the ' Coralline 

 Beds ' of Dundry) : a comparison of the recorded Brachiopod-fauna 

 of the Truellii-Beds of Dorset-Somerset 1 with that from the 

 c Coralline Beds ' of Dundry 2 gives weight to this suggestion. 



1 'Bajocian of the Mid-Cotteswolds' Quart. Journ. Geol. Soc. vol. li (1895) 

 p. 440. 



2 ' Dundry Hill ' ibid. vol. lii (1896) p. 698. 



