BITTIUM RBTTCULATUM. 415 



1873-5. Cerithiolum reticulatum, Seguenza, Boll. R. Coin. Geol. Ital., vol. iv, p. 348, no. 220, 1873; 



vol. vi, p. 344, no. 420, 1875. 

 1884. Bittium reticulatum and vars , Bucquoy, Dautzenberg et Dollfus, Moll. mar. Rouss., vol. i, 



p. 212, pi. xxv, figs. 1—27. 

 1886. Bittium reticulatum, Dollfus et Dautzenberg, Feuilles cles jeunes Nat., vol. xvi, p. 105. 

 1890. Bittium reticulatum, Carus, Prod. Faun. Medit., vol. ii, p. 360. 

 1892. Bittium reticulatum, Locai'd, Coq. mar. Cotes de Fiance, p. 120, fig. 108. 



1895. Bittium reticulatum and vars., Sacco, Moll. Terr. Terz. Piem., pt. xvii, p. 38, pi. ii, figs. 105 — 14. 

 1898. Cerithium reticulatum, A. Bell, Trans. Roy. Geol. Soc. Cornwall, vol. xii, p. 143. 

 1901. Bittium reticulatum, Br^gger, Norges geol. Unders^gelse, no. 31, p. 661, pi. ix, fig. 8. 

 1901-7. Bittium reticulatum, Scalia, Atti Accad. Gioen. Sci. Nat. Catania, vol. xiv, p. 13, no. 151, 



1901 ; vol. xx, p. 34, no. 227, 1907. 

 1908. Bittium reticulatum, Kobelt, Icon, scbalentrag. europ. Meeresconcli., vol. iv, p. 101,pl. cxviii, 



figs. 1—10. 

 1910. Bittium reticulatum, 0yen, Kongl. Norske. Vid. Selsk. Skrift., no. 9, pp. 16, 31, 34. 

 1912. Bittium reticulatum, Cerulli-Irelli, Palaeont. Ital., vol. xviii, p. 143, pi. xxiii, figs. 12-22. 



Specific Characters. — Shell small, slender, forming an elongated pyramid with 

 a narrow base and an acute apex, rather solid; whorls 15 — 16, in the British 

 variety, both recent and fossil, but slightly convex, regularly tapering, the last 

 about one-third the total length ; ornamented by 3 — 4 thread-like spiral ridges, 

 crossed by numerous longitudinal ribs which become granulate at the points of 

 contact and are sometimes varicose but do not extend below the periphery ; suture 

 well-marked but not deep : mouth ovate, angulated above, rounded below ; basal 

 groove shallow, rather wide, turning to the left; columella short and flexuous. 



Dimensions. — L. 12 mm. B. 4 mm. 



Distribution. — Recent: common on the western and southern coasts of Great 

 Britain and Ireland, abroad from the Lofoten islands to the Canaries. Mediter- 

 ranean, Adriatic and iEgean. 



Fossil ; St. Erth. Newbournian Crag : Ramsholt. Icenian : 

 Norwich, Aldeby. 



Pleistocene: Kelsey Hill, Nar Valley, Selsey (A. Bell), Torbay, Bridgewater. 

 Scotland, passim. Ireland, Dublin, estuarine clays of Belfast (very common). 



Holocene : Portrush. 



Miocene: France, Italy, Vienna basin. 



Lower Pliocene : Biot, Piedmont, Ligurian coast, Siena. 



Upper Pliocene : northern Italy, Monte Mario, Altavilla. 



Pleistocene : Livorno, Taranto, Reggio, Messina, Monte Pellegrino, Ficarazzi, 

 Catira, Nizzeti. Denmark. Uddevalla. Tapes-banks : Christiania, Trondhjem. 

 Eemien : Holland. 



Remarks. — The present species, formerly known as Cerithium reticulatum, has 

 been taken of late years as typical of the genus Bittium, a distinct group of small 

 Cerithiidae, which are elongate, turreted and many-whorled, with granulated 

 sculpture, a very short canal and a rounded base. 



54 



