TRANSACTIONS OF SECTION C. 675 



Omitted from Notice in 1889. 



Brew, F. Is there Coal under London ? Science for All, vol. v. pp. 324-328. 



Firket, A. Sur I'Extension en Angleterre dii Bassin houiller Franco-Beige. 

 Ann. Soc. Geol. Belg., t. x. Bullefin, pp. xcii-xciv (1883). 



Taylor, W. On the Probability of Finding Coal in the South-East of England, 

 pp. ii., 22, 8vo. Reigate (1886). 



Topley, W. On the Correspondence between some Areas of Apparent Upheaval 

 and the Thickening of Subjacent Beds. Quart. Journ. Genl. Soc, vol. xxx. see pp. 

 186,190-195(1874). See also Memoir 'The Geology of the Weald,' pp. 241, 242, 

 pi. vi. (1875). 



The following Papers were read : — 



1. The Southern Character of the Molluscan Fauna of the CoraUiyie Crag 

 tested by an analysis of its characteristic and abundant species. By 

 F. W. Haemer, F.G.S. 



Out of 436 species of Mollusca from the Coralline Crag, excluding varieties 

 given in Mr. Searles Wood's monograph, nearly 90 are represented by unique 

 specimens only, and more than 100 others are very rare. Some of these rarer 

 forms may be only locally so, although, with few exceptions, all the species which 

 are common in the Belgian Pliocene beds, of similar age to the Coralline Crag, 

 are common also in that deposit. An analysis of all the shells in any horizon of 

 the Crao- in which the same value is attached to forms which are exceedinglj' rare, 

 and to those which occur in countless profusion, is apt to be, to some extent, mis- 

 leading. The Southern character of the fauna of the Coralline Crag, and its close 

 resemblance to that of the Mediterranean, is much more strongly evidenced when 

 we confine our enquiry to the more abundant shells of this deposit. 



Omitting the rare species, we have 240 which may be I'egarded as characteristic 

 forms. Of these 89, or about 37 per cent., are regarded by Mr. Wood as extinct, 

 and eight others may be, for our present purpose, taken as such, as they have 

 ceased to exist in European seas, and are only found in parts of the vvorld more or 

 less distant. Of the 143 species remaining, there is only one, liiiccinum {Biiccin- 

 opsis) Dalei, which is not now found living, either in the Alediterranean or the 

 West European area, which Dr. Gwyn Jeffreys said cannot be regarded as zoolo- 

 gically distinct from it. This shell cannot, however, be looked on as a boreal 

 species, as it is given by M. DoUfus as occurring in the Miocene beds of Touralne. 

 Thirty-three of the extinct shells of the Coralline Crag are also found in the Medi- 

 terranean Pliocene, either at Monte Mario, or Biot, near Antibes. Altogether 170 

 species out of 396 found at Monte Mario are common to that deposit and to the 

 Coralline Crag, a larger proportion than is the case with the Diestien beds of Bel- 

 gium. The practical identity thus shown between the Molluscan fauna of the 

 Coralline Crag, and that of the Mediterranean and West European province, and 

 the close resemblance bytween both of them and some of tlie Italian Pliocenes, 

 point to a more direct and open communication between the Mediterranean and 

 the seas of Great Britain at .some period subsequent to the coming into existence 

 of the present fauna than exists at present. 



The distinctly Southern character of the Mollusca of the Coralline Crag is evi- 

 denced by the comparatively small proportion of the species which range north- 

 wards into British waters, and this also comes out more strongly when we confine 

 ourselves to its more abundant forms. While there is only one which is British, 

 and not Southern, there are 42, or 29 per cent., of the European species which 

 are Southern and not British. There are, however, nine shells which are charac- 

 teristic Mediterranean species, and are only included in lists of the British Mol- 

 lusca because of the occasional discover}' ot some rare specimen on our coasts. If 

 we regard these nine species as Mediterranean, it raises the proportion of exclu- 

 sively Southern forms to 36 per cent. The abundant shells are practically all 

 Southern, and if it were possible to count shells, and not species, we should meet 



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