to MIDDLE ALBIAN STRATIGRAPHY 



which no structural significance should be attached : depositional controls on sedi- 

 mentation will also be discussed later. The sections in the Weald are described first, 

 then the Isle of Wight, Dorset coast, and the outcrop from Devon to the Leighton 

 Buzzard area of Bedfordshire. The Albian sediments of the Leighton Buzzard area 

 and of East Anglia are to be described elsewhere, but in no way do they affect the 

 stabilising of the Albian Zonal scheme. Borehole evidence in southern England is 



Table i 



Ammonite zonal scheme of the Middle Albian adopted here and discussed in detail on pages 

 118-130. 



Substage 



Upper 

 Albian 



(part) 



Middle 

 Albian 



Zone 



Mortoniceras inflatum (part) 



Euhoplites lautus 

 Euhoplites loricatus {2) 



Hoplites (H.) dentatus 



Subzone 



\ 



Hysteroceras orbignyi 

 I Diftoloceras cristatum < - l) 



{Anahoplites daviesi 

 Euhoplites nitidus 



f Euhoplites meandrinus 

 J Mojsisovicsia subdelaruei 

 Dimorphoplites niobe 

 Anahoplites inter medius 





f Hoplites (Hoplites) spathi 

 J Lyelliceras lyelli (3) 

 Hoplites (' Isohoplites ') 

 eodentatus 



C Protohoplites puzosianus w 

 < Otohoplites raulinianus 



(1) Formerly included in the lautus Zone sensu Spath (e.g. 1941 ; 668). 



(2) First recognised by Owen (1958 ; 162). 



(3) Approximately equivalent to the benettianus Subzone of Spath non De Ranee (1868). 



(4) In better developed sequences in France (Pays de Bray, Aube) , this index fossil does not range up 

 to the base of the eodentatus Subzone. 



Lower 



" Douvilleiceras 



Albian 



mammillatum 



(part) 



(part) 



then considered before attention is turned to the Paris Basin. A detailed compar- 

 ison is made between the sections at Folkestone and Wissant (Pas de Calais) . Selected 

 sections in the Meuse, Marne, Haute Marne, Aube, Yonne, and in the Pays de Bray, 

 are described followed by a comparison of sections in the Pays de Caux with the Isle 

 of Wight. The ammonite zonal and subzonal scheme employed in this account is 

 given in Table 1 above. 



