R. M. Brydone — Zone of 0. pilula, S. English Chalk. 509 



that the British evidence shows only local features due to melting/ 

 F. W. Harmer ^ believes that "a considerable interval" may have 

 separated the invasion of the Scandinavian ice from the epoch of local 

 glaciation. P. G. H. BoswelP agrees witli Lamplugh that the middle 

 sands and gravels of Eastern England represent a vicissitude, but not 

 a "mild Interglacial Period". We venture to think that these 

 authors, had they lived in early Pleistocene times, would have 

 welcomed an epoch of rain and fluvioglacial flooding, with the 

 temperature above 0° C, like that of summer in Spitsbergen, after the 

 aerial hoar-frost and dry ice-surfaces of an ice-age, and would have 

 felt that the new conditions could no longer be described as glacial. 

 The Wexford gravels have already played their part in controversy. 

 This fresh examination of them may prove of service in bringing that 

 controversy to a close. 



TI. — The Zone of Offasteh filula in the South English Chalk. 



By E. M. Bkydone, B.A., F.G.S. 



{Continued from p. 457.) 



IV. General Conclusions.* 



I CLAIM to have now shown that the zone of O.pilula as established 

 in 1912 for Hants and the Salisbury area holds good in its broad 

 features also for Sussex, the Isle of Wiglit, and Dorset, and that it is 

 almost equally constant in some of its minor features, especially the 

 way in which it ends in a bed 2 ft. 6 in. to 3 feet thick with a flint 

 seam in the middle of it and enclosed by two marl seams. I am only 

 prevented by a single section in Hants from setting this up as the 

 universal rule in all sections I have seen. In Tlte Stratigraphy 

 I assigned pits Nos. 1065, 1066, and 1067, the last of which will be 

 more readily recognized as Mottisfont Whiting Pit, to the zone of 

 A. qxiadratus, because on examining them for the purposes of that work 

 for the first time since 1892 I had failed to find evidence of more than 

 a seam of O.pihda without any others of the associated fossils of the 

 zone. At the time of that examination all the pits weie in a most 

 unfavourable condition. Since then I have been keeping regular watch 

 on the Whiting Pit (No. 1067), and I soon found that the subzone of 

 abundant O.pilula must be represented at its base, and then that the 

 upper belt of 0. pilula in that subzone must be exposed : ^ but it was 

 only this spring that I was able to fix the absolute position of the 



^ " The Interglacial Problem in the British Islands " ; paper printed at the 

 Congres geol. internat. at Toronto, 1913. 



2 Discussion on paper by P. G. H. Boswell, Quart. Jomn. Geol. Soc, vol. Ixix, 

 p. 581, 1913. 



'^ " On the occurrence of the North Sea Drift " : Proc. Geol. Assoc, vol. xxv, 

 p. 129, 1914. 



'' Part I appeared in the August Number, pp. 359-69 ; Part II, September, 

 pp. 405-11 ; Part III, October, pp. 449-57. 



^ The specimen of A. vcrus recorded from this pit and assigned to the zone of 

 A. quadratus in The Stratigraphy of the Chalk of Hants, p. 99, may there- 

 fore have come from the uppermost beds of the zone of 0. pilula ; but the 

 odds are in favour of the zone of A. qiiadratus, which occupies three-fourths 

 of the pit. 



