i 4 MIDDLE ALBIAN STRATIGRAPHY 



doubted deposits of spathi and intermedins Subzone age. There is no break apparent 

 in sedimentation, but the only common fossils are large Inoceramus concentricus. At 

 localities such as Petersfield (Sussex p. 34), Osmington (Dorset p. 51), Devizes (Wilt- 

 shire p. 60), and to a point also in the southern part of the Paris Basin (pp. 88,93,97) this 

 gap in the Weald sequence is filled. There is indeed the association of Anahoplites 

 and Hopiites (H.) but the forms of Anahoplites are very distinct and include A . grims- 

 dalei sp. nov. and A. osmingtonensis sp. nov. ; forerunners of the evolutus-intermedius- 

 praecox group. Hopiites (H.) continues on into the intermedins Subzone but is a very 

 subordinate element in the fauna. 



The classification of the remainder of the Lower Gault at Folkestone by Spath has 

 seen only a few modifications (Owen 1958 : i960 ; 376-7). Spath pointed out (1926b ; 

 421) that the divisions between Subzones do not always coincide with the junction 

 between beds. The details of Bed I (vi-vii) given by the writer in 1958 were taken 

 from what are now obviously disturbed sections, but were then the best available, 

 and should be discounted. The account given in 1963 was taken from a perfect 

 section. Bed I (vii) and the whole of Bed II up to a level 3 inches (0-70 m.) below 

 its top, are classified with the intermedins Subzone. The bulk of the ammonites are 

 crushed and consist essentially of species of Anahoplites such as A. intermedins, 

 A. praecox, and A. mantelli. Partly phosphatised ammonites occur in Bed II (i) and 

 pyritic specimens occur very sparingly among the numerous crushed fossils in II (ii) . 

 The fauna of these three subdivisions is very uniform, but in II (iii) we see the intro- 

 duction of a particularly coarse development of A. praecox, and in II (iv), where 

 ' solid ' pyritic fossils are more common, Euhoplites pricei Spath is a very character- 

 istic form. 



Dimorphoplites niobe Spath, already present in the intermedins Subzone, becomes 

 common in the shell seam about 3 inches (0-076 m.) below the base of Bed III at which 

 level Anahoplites of the praecox-intermedius group quite suddenly ceases to be im- 

 portant. D. niobe, together with A. planus and A. spiendens then characterises the 

 whole of Bed III, within the upper 2 to 3 inches (0-051-0-076 m.) of which, part or 

 wholly phosphatised fossils with the nacreous shell occur sparingly. Bed IV (i) does 

 not mark a great break in the sequence although semi-derived phosphatic fragments 

 of fossils do occur. D. niobe, A. planus and A. spiendens still occur but the fauna 

 becomes more diversified and Mojsisovicsia subdelaruei M. remota and M. spinulosa 

 (Spath) appear as infrequent but highly characteristic species. These species of 

 Mojsisovicsia occur indigenous in both IV (i) and (ii) which are classified with the 

 subdelaruei Subzone (Owen i960 ; 376). Bed IV (iii) marks a greater period of 

 erosion and its characteristic ammonite fauna was listed by Owen (1958 ; 157). This 

 bed, together with the basal 2 inches (0-051 m.) of Bed V which contains the same 

 fauna is classified with the meandrinus Subzone. Casey {in Smart, Bisson & Wor- 

 ssam 1966 ; 109) and in effect Milbourne {in Hancock 1965 ; 247) state that Euhoplites 

 meandrinus Spath occurs outside Bed IV (iii) and the basal part of Bed V. However, 

 the author has never seen a specimen, either in the field or in the collections, from any 

 other bed. Spath's original (BMNH, C 32306) was a pyritic specimen, now decom- 

 posed, which with very little doubt came from the basal part of Bed V, as Spath 

 thought likely (1930b ; 271). 



