324 Notices of Memoirs — R. Bullen Newton — 



of Red Crag age, although he observed that "the character of the 

 mollusca, as a whole, is essentially southern, no peculiarly Arctic 

 shell having as yet occurred". 



The fauna was more particularly described by Professor Kendall 

 and R. G. Bell l in the following year and again referred to as con- 

 temporary with that of the Red Crag, a result contrary to the views 

 of Mr. Reid, who claimed a greater age. Since that discussion 

 Mr. Alfred Bell 2 has published a paper on the St. Erth Mollusca and 

 regarded their age as Mio- Pliocene or Messinian, a somewhat similar 

 horizon having already been partially suggested by Gwyn Jeffreys, 3 

 who stated : " He was not clear whether the St. Erth deposit was of 

 Older Pliocene or possibly of Upper Miocene age." In the same 

 paper Mr. A. Bell placed upon record an important opinion he had 

 received from M. Dollfus, which reads as follows : " You have in 

 St. Erth exactly the same Pliocene fauna as we have at Gourbesville 

 in the Cotentin," a statement more or less confirming the previous 

 researches of Mr. Reid (1890), who had acknowledged the necessity 

 of a strict comparison between the molluscan species of Gourbesville 

 and those of the St. Erth deposits, as the fossils from the former 

 locality "point to conditions very similar to those indicated by the 

 shells from St. Erth". The Gourbesville fauna, however, as 

 previously mentioned, is now considered to be of Miocene age 

 (Tortonian or Messinian). About fifty per cent of the Lenham shells 

 are extinct species, a somewhat similar percentage marks the Box- 

 stone fauna (according to a calculation made from Mr. A. Bell's 

 memoir in Journ. Ipswich Pield Club, vol. iii, pp. 7, 8, 1911), and 

 Mr. Reid (Survey Memoir, 1900, p. 64) has stated that the Coralline 

 Crag and St. Erth deposits contain each about forty per cent of 

 extinct shells. It will be observed that there is a similarity running 

 through these percentages of extinct forms, which appears to furnish 

 satisfactory evidence for regarding the four stages of Mr. Reid's 

 "Older Pliocene" group as of the same approximate geological age, 

 although the Box-stones, as before explained, may be somewhat older. 



From the foregoing details of the different faunas involved in this 

 discussion, it is certain that many of the species had their origin in 

 Miocene times. There is good reason for recognizing the St. Erth 

 shells as of Miocene age, because of their relationship to species 

 characterizing the French Redonian. Similarly, the Box-stone fossils 

 would belong to the same period, as their affinities are with those of 

 the Bolderian of Belgium, which is generally regarded as Tortonian 

 or Upper Vindobonian. 



Lastly, the Lenham fauna with its strong Vindobonian and Coralline 

 Crag facies should also be placed in the Miocene, and in consideration 

 of its relationship to that characterizing the Upper Miocene deposits 

 of Northern Germany and the Anversian beds of Belgium, I would 

 recognize it as belonging to the latest or Messinian stage of the 

 Miocene, which is synonymous with the term Mio-Pliocene. The 

 stratigraphical name of Mio-Pliocene was introduced into Belgian 



1 Quart. Journ. Geol. Soc, vol. xlii, pp. 201-14, 1886. 



2 Trans. Roy. Geol. Soc. Cornwall, vol. xii, p. 133, 1898. 



3 Quart. Journ. Geol. Soc, vol. xli, p. 72, 1885. 



