416 PLTOCENE MOLLUSC A. 



Prof. Sacco states that this form is abundant in the Upper and Lower Pliocene 

 of northern Italy. Sign. Cerulli-Irelli reports it from Monte Mario, A. Bell from 

 Biot, Seguenza from Altavilla, and from a number of Pleistocene localities in 

 Sicily and southern Italy, and Dr. Scalia from the sub-Etnaen deposits of Catira 

 and Nizzeti. It is common as a recent shell on the southern and western coasts of 

 Great Britain, ranging from the Lofoten Isles to the Canaries and to the ^Egean, 

 occurring also in many Pleistocene deposits in this country, as well as in those of 

 Scandinavia. It is rare, however, in the English Crag and has not been reported 

 from that of Belgium or Holland. 



The specimen figured by Wood was from the Nar brick-earth (late Pleisto- 

 cene) ; one of those here given (fig. 2), which shows the varicose ribs characteristic 

 of the present species, is from the Icenian Crag of Aldeby, the other from the 

 Newbournian of Ramsholt. 



Var. trinodosa (Etheridge and A. Bell). Plate XLI, fig. 4. 



1885. Cerithium reticulatum, S. V. Wood, Quart. Journ. Geol. Soc, vol. xli, p. 70. 



1886. Cerithium reticulatum , var , Kendall and R. G. Bell, Quart. Journ. Geol. Soc, vol. xlii, p 211. 

 1898. Cerithium (Bittium) reticulatum, var. trinodosa (jpseudoreticulatum, S. V. Wood, MS.), A. Bell, 



Trans. Roy. Geol. Soc. Cornwall, vol. xii, p. 143, pi. i, fig. 13. 



Varietal Characters. — Differs from the type in having three rows of nodules 

 instead of four, a longer spire and a deeper suture ; the base is encircled by two 

 thin prominent ridges and there is usually a fine thread on the body-whorl between 

 the two upper rows. 



Dimensions. — L. 14 mm. B. 3 mm. 



Distribution. — Recent : southern coast of England (A. Bell). 

 Fossil : St. Erth. 



Remarks. — This is one of the most abundant forms of the St. Erth fauna, being- 

 found in all our collections from that place. Mr. A. Bell informs me that in a 

 letter received from M. Dollfus the latter said " perhaps it is a new species." The 

 former states he has seen two recent specimens, very much like the St. Erth 

 fossils, which had been picked up on our southern coast. 



Bittium lacteum (Philippi). Plate XLI, figs. 7, 8. 



1836-44. Cerithium lacteum, Philippi, Enura. Moll. Sic, vol. i, p. 195, 1836 ; vol. ii, p. 162, 1844. 

 1868. Cerithium elegans, Weinlcauff (non Blainville), Conch. Mittelm., vol. ii, p. 164. 

 1872. Cerithiopsis lactea A S. V. Wood, Mon. Crag Moll., 1st Suppl., p. 52, pi. iv, fig. 16. 

 1878-84. Cerithiolum lacteum, Monterosato, Enum. e Sinon. Conch. Medit,, p. 38, 1878 ; Nom. Gen. 

 e Spec Conch. Medit., p. 122, 1884. 



