The Warminster Greensand Fossils. 



273 



that the fauna which they rightly regard as so essentially Cenomanien, 

 is not a tj'pical Upper Greensand fauna, nor even the fauna of the 

 Greensand chert beds ; but is the fauna of a special bed which lies 

 only just below the horizon that is taken by Mr. Hill and myself 

 as the base of the Cenomanian both in France and England. 1 



The fact that this bed contains so many precursors of the Chalk 

 Marl (or Cenomanian) fauna does not seem to me a sufficient reason 

 for excluding it from the Upper Greensand ; though doubtless most 

 French geologists would think so. D'Orbigny's doctrine, that every 

 system can be divided into stages, the faunas of which are sharply 

 marked off from one another, has greatly influenced French opinion, 

 and they still seem to have a tendency to put a higher value upon 

 the evidence of fossils than upon other lines of evidence. 



My own experience as a field geologist has taught me that 

 exposures which are twenty or thirty miles apart, generally show 

 some little differences in the distribution of fossils, above and 

 below any line of separation which can be taken between two 

 stages. When localities are still further apart, the range of species 

 differs more; no one now supposes that a species appeared every- 

 where at the same epoch of time, and we must not allow the evidence 

 of fossils to override plain stratigraphical facts. 



Appendix. 



The following is a list of the species to which the specimens 

 preserved in brownish phosphate included in many collections of 

 Warminster fossils belong. It will be seen that many species have 

 been excluded on this account from the previous lists ; but there is 

 no doubt that some occur both in the matrix of the Eye Hill Sand 

 and in that of the Chloritic Marl, though all are more common in 

 the latter. 



Ammonites Coupei, Brong. 



„ curvatus, Maut. 



,, falcatus, Mant. 



, , complanatus ? 



„ Mantelli, Sow. 



,, navicularis, Mant. 



,, planulatus, Sow. 



,, varians, Sow. 



Scapbites requalis, Sow. 

 Turrilites Bergeri, Brong. 



,, costatus, Lam. 



„ Gravesianus, D'Orb. 



„ Morrisii, Sbarpe. 



,, tuberculatus, Bosc. 

 Nautilus Deslongchampsianus, D'Orb. 



,, Fittom, Sbarpe. 

 Avellana cassis. 

 Aporrbais Parkinsoni ? and otber 



species. 

 Columbellina, sp. 

 Emarginula Gresslya, P. and C. 



„ sp. 

 Dentalium ellipticum, Sow. 



Crepidula, sp. 

 Fusus bilineatus ? 



„ sp. 

 Pleurotornaria Rhodaui, D'Orb. 



,, Thurmanni, P. and R. 



,, vraconnensis, P. and C. 



Phasianella, sp. 

 Turbo, sp. 

 Solarium Martinianum, D'Orb. 



,, dentation, D'Orb. 



,, ornatum, Sow. 

 Scalaria Rauliuiana, D'Orb. 

 Natica gaultina, D'Orb. 

 Pterocera inflata, D'Orb. 

 Luculliva glabra, Park. 



,, ligerieusis ?, D'Orb. 

 Area Mailleaua, D'Orb. 

 Cyprina quadrata, D'Orb. 

 Unicardium Ringmeriense, Mant. 

 Nucula pectinata, Sow. 

 Lutraria carimi'era, D'Orb. 

 Catopygus columbarius, Lam. 



1 See Quart. Journ. Geol. Soc, vol. lii, pp. 105, 119. 



DECADE IV. VOL. III. NO. VI. 



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