L^OCOCHLIS GRANOSA. 427 



Genus LiEOCOCHLIS, Danker and Metzler, 1874. 

 Laeocochlis granosa (S. V. Wood). Plate XLI, figs. 11—13. 



1842-8. Cerithium granosum, S.V.Wood, Ann. Mag. Nat. Hist. [1], vol. ix, p. 538, 1842; Mon. 

 Crag Moll., pt. i, p. 73, pi. viii, fig. 9, 1848. 



1871. Cerithium granosum, Jeffreys in Prestwicli, Quart. Jouru. Geol. Soc, vol. xxvii, pp. 142, 487. 



1872. Cerithium granosum, A. and R. Bell, Proc. Geol. Assoc, vol. ii, pp. 203, 209, 213. 



1874-84. Cerithium sinistratum, Van den Broeck, Ann. Soc. Eoy. Malac. Belg., vol. ix, pp. 134, 



292 ; C. granosum, p. 351, 1874 ; vol. xix, p. 26, 1884. 

 1881. Cerithium sinistratum, Nyst, Conch. Terr. Tert. Belg., p. 78, pi. vi, fig. 9. 

 1899. Lxocochlis granosa, Norman, Ann. Mag. Nat. Hist. [7], vol. iv, p. 152. 

 1906. Leeocochlis granosa, Cossmann, Ess. Paleoconch. compar., vol. vii, p. 155. 



Specific Characters. — Shell sinistral, turreted, elongate; whorls 10 or 12, 

 somewhat convex, the last about one-third the total length, excavated below ; 

 suture well-marked, oblique ; spire gradually diminishing in size towards a blunt 

 apex ; ornamented (in the Crag variety) by longitudinal and transverse ridges of 

 equal value, giving the shell a regularly reticulated appearance, tuberculate at the 

 points of intersection; in a recent and allied form (var. Macandrewse oi Dautzenberg 

 and Fischer) the longitudinal ribs are generally obsolete or nearly so, being, when 

 present, very fine and inconspicuous and confined to the upper whorls; base without 

 sculpture ; mouth oval ; canal short, twisted, turning to the right. 



Dimensions. — L. 15 — 30 mm. B. 4— 8 mm. 



Distribution. — (Of Crag form) Not known living. 



Fossil : Coralline Crag : Gedgrave, Sutton. Waltonian : 

 Walton-on-Naze, Beaumont, Little Oakley. Newbournian : Bentley, Newbourn, 

 Waldringfield. Butleyan : Butley. 



Casterlien, Scaldisien, Poederlien : Belgium. 



Remarks. — In 1848 the present species was only known as a Crag fossil from 

 one or two localities, but it has been recorded since then from all our East Anglian 

 Pliocene horizons, from the Gedgravian to the Butleyan. I have obtained, for 

 example, nearly forty specimens, most of them broken, at Oakley. The Belgian 

 fossil from the Scaldisien of Antwerp, described by Nyst in 1881 as C. sinistratum, 

 is probably the same, though Jeffreys at first thought it different, but as he 

 afterwards identified some specimens in the Brussels Museum with our shell, a 

 more probable explanation seems to be that Nyst's figure was more or less inaccurate. 

 M. Van den Broeck's latest opinion was that the Belgian and English shells were 

 identical. 



The Crag species has been identified since 1878 by G. O. Sars, Jeffreys, and 

 Friele with a recent and northern shell, Triforis Macandrewse, H. and A. Adams, 

 and with Lseococklis Poiuvieranise, Dunker and Metzler, the latter authorities having 



