52 MIDDLE ALBIAN STRATIGRAPHY 



There is, therefore, no evidence of the presence of Upper Albian sediments in 

 Lang's Bed 3 and this is consistent with the distribution of Inoceramus concentricus 

 and i". sulcatus. I. concentricus is known from Beds 1, 2, and 3 (e.g. Lang Colin., 

 BMNH., L 55076 from Black Ven) both on Black Ven and Stonebarrow. Specimens 

 of I. sulcatus are known from Black Ven (e.g. BMNH., L 55368-71 Grimsdale Colin.) 

 preserved without the shell in glauconitic sandstone which suggests Lang's Bed 10, 

 certainly no lower horizon. The record of Anahoplites planus from Lang's Bed 10 by 

 Spath (1943 ; 744) is an error. The Middle-Upper Albian boundary falls somewhere 

 between the top of Bed 3 and ?the base of Bed 10. 



The above indicates that Kitchin & Pringle's statement that no Lower Gault 

 exists at Black Ven is quite fallacious (1922 ; 163). This statement is the more 

 incredible when one realises that they had never examined the section and apparently 

 had overlooked Lang's paper of 1914. There may well be a non-sequence in these 

 sections but at this time there is no evidence to indicate its extent. 



No sections further west on the Devon Coast have been examined by the writer. 



(iv) CONCLUSION 



The poor state of the sections in the Isle of Wight and on the Dorset Coast are 

 particularly tantalising, nonetheless, some results can be drawn from this incomplete 

 information. It is apparent that in the Isle of Wight the eodentatus Subzone is 

 represented at the summit of the Carstone ; the lyelli Subzone is represented in the 

 lower part of the Gault at least in the southern part of the island ; and the spathi 

 Subzone sediments are well developed. The intermedins Subzone is probably repre- 

 sented but the conclusive proof is not yet to hand. 



By Worbarrow Bay and Osmington the fossiliferous concretions very near the 

 base of the Formation are of uppermost spathi Subzone age, and there is evidence of 

 lautus Zone sediments near the top of the Gault in the Osmington- White Nothe area. 

 In the sea-truncated outliers between Seatown and Lyme Regis the lowest fossilifer- 

 ous sediments are of intermedins Subzone age. As one proceeds westwards from the 

 Isle of Wight, therefore, the lowest fossiliferous sediments become later in age (text- 

 fig. 23). The intermedins Subzone is widely represented by sediments in the deeper 

 parts of the Wessex Basin ; for example in the Petersfield and Winchester districts, 

 Hampshire (p. 69), at Didcot, Berkshire (p. 63), Devizes, Wiltshire (p. 60), and 

 possibly at Okeford Fitzpaine, Dorset (p. 56). Its presence in the Isle of Wight, and 

 in the Dorset coast sections as far west as Osmington should not be discounted. 

 Across the Channel at Cauville on the French coast NE. of Le Havre, there occurs, 

 above a remanie bed of basal dentatus Zone age, even later sediments of niobe Subzone 

 age (p. 107). 



C. The outcrop from Devon to Bedfordshire 



There is no information available about Middle Albian sediments inland in the 

 area W. of the River Axe. Neither is there any further stratigraphical information 

 available at the outcrop from the valley of the Axe to Okeford Fitzpaine, N. Dorset, 



