572 PLIOCENE MOLLUSGA. 



Turbonilla (Pyrgostelis) ignota, sp. nov. Plate XLIX, fig. 41. 



Specific Characiers. — Shell minute, slender, oblongo-conical; whorls 8, flattened, 

 slightly compressed at the apex, gradually increasing doAvnwards, the last whorl 

 about one-third the total length ; ornamented by straight longitudinal costas which 

 die out before reaching the base, and by fine inconspicuous stride in the interspaces 

 between the ribs ; suture oblique, well-marked, but not deep ; mouth oval, small. 



Dimensions. — L. 3 mm. B. 1 mm. 



Distribution. — Not observed living. 



Fossil : Coralline Crag : Gedgrave. 



Ueinarhs. — The specimen here given belongs to the York Museum where it 

 bears Wood's name of Cliemnitzia elegantior, to which species it presents a superficial 

 resemblance. When examined under the microscope, however, our shell may be 

 seen to be distinctly marked with short ridges in the interspaces, Avhich do not 

 cross the ribs — a feature entirely absent from the figure of the fossil represented in 

 Wood's Monograph. Many specimens from the Crag are considerably worn so that 

 the finer part of the sculpture is obliterated. It is possible, therefore, that the 

 present form may occur in other localities where it has escaped notice. 



Siti>-r/cmts PYRGOLIDIUM, Monterosato, 1884. 

 Turbonilla (Pyrgolidium) internodula (S. V. Wood). Plate XLIX, figs. 33, 34. 



1848—72. Chemnitzia internodula, S. V. Wood, Mon. Crag Moll., pt. i, p. 81, pi. x, fig. 6, 1848 ; 1st 



Suppl., pt. i, p. 60, 1872. 

 1864. Chemnitzia corbis, Couti, 11 Monte Mario ed i suivi foss. subap., p. 30. 

 1870. Chemnitzia internodnla, S. V. Wood, Jr., and F. W. Harmer, Traus. Brit. Assoc. (Liverpool), 



p. 90. 

 1871 — 7.3. Chemnitzia internodnla, Jeffreys in Prestwich, Quart. Journ. Geol. Soc, vol. xxvii, pp. 143, 



487, 1871 ; Rep. Brit. Assoc. (Bradford), p. 114, 1873. 

 1872. Chemnitzia internodnla, A. and R. Bell, Proc. Greol. Assoc, vol. ii, pp. 203, 209, 216. 

 1873—76. Turbonilla internodula, Segueuza, Boll. R. Com. Geol. Ital., vol. iv, p. 354, no. 312, 1873 ; 



vol. vii, p. 92, no. 542, 1876. 

 1879. Chemnitzia internodula, Jas. Reeve, Proc. Norwich Greol. Soc, vol, i, p. 70. 

 1881. Tnrbonella internodula, Nyst, Couch. Terr. tert. Belg., p. 73, pi. vi, fig. 3. 



1892. Turbonilla internodula. Van den Broeck, Bull. Soc. Belg. GcoL, vol. vi (Mcnioii-es), pp. 122, 132. 

 1892 — 1904. Turbonilla (Pyrgolidium) internodulum and vars., Sacco, Moll. T*?rr. Terz. Piera., pt. xi, 



p. 84, 1892 ; pt. XXX, p. 109, pi. xxiv, figs. 16, 17, 1904. 

 1896. Turbonilla internodula, Bernays, Bull. Soc. Belg. Geol., vol. x (Mcmoires), p. 131. 

 1912. Turbonilla internodula, Tesch, Med. v. d. Rijks. v. Delfstoffeu, No. 4, p. 72, no. 167. 

 1914. Turbonilla (Pi/rgolidium) internodula, Cerulli-Irelli, Palaeont. Ital., vol. xx, p. 277, pi. xxiii, 



figs. 68, 69. 



Specific Characters. — Shell small, slender, subulate, subcylindrical ; whorls 

 about 12, flattened; ornamented by numerous longitudinal costfe, varying in 



