638 PLIOCENE MOLLUSCA. 



Mr. Bell lias described a variety (rigida), also from St. Brth, without teeth, and with 

 a slighter umbilicus ; this, he thinks, may be immature. 



Var. picta (Btheridge and Bell). Plate LI, fig. 35. 



1893-98. Rissoaj^entodonta, vnr. jiicta, A. Bell, Proc. Eoy. Irish Acad. [3], vol. ii, j). 630, 1893; 

 Traus. Eoy. Geol. Soc. Cornwall, vol. xii, p. 153, 1898. 



Bemarkfi. — This specimen is the one originally described by Mr. Bell as a 

 variety of li. peiitodonta. When first found it was characterised by colour-bands 

 and irregular streaks which have now disappeared though they aie still represented 

 by inconspicuous and nearly obsolete costge. From this variety and from the var. 

 rigida the five teeth of the type form are wanting. 



Var. rigida (Etheridge and Bell). Plate LI, fig. 36. 



1893-98. Bissoa 2)entodonta, var. rigida, A. Be}], Froc. Eoy. Irish Acad. [3], vol. ii, p. 630, 1893; 

 Trans. Eoy. Geol. Soc. Cornwall, vol. xii, p. 153, 1898. 



Remarks. — Mr. Bell has described this specimen, which is from the British 

 Museum, as a variety of Ii. ijentodonta. It wants the teeth characteristic of the 

 type, the umbilical chink is smaller, and when first found it had a colour-band on 

 the periphery. 



Cingula conuloidea (Etheridge and Bell). Plate lil, fig. 44. 



1898. Bissoa (Onoba) conuloidea, A. Bell, Trans. Eoy. Geol. Soc. Cornwall, vol. xii, p. 154. 



Specific Characters. — Shell minute, solid, forming a truncated cone with an 

 exceedingly small, isolated and pointed apex ; whorls 4, smooth, flattened ; spire 

 elongate, sub-cylindrical, regularly tapering ; suture slight ; mouth ovate, angulated 

 above, peristome well marked, continuous. 



Dimensions. — h. 2 mm. B. 1 mm. 



Distributiov. — Not known living. 

 Fossil : St. Erth. 



Remarks. — The specimen here figured is the one ol)tained by Mr. A. Bell at 

 St. Erth, and described by him under the above name. It seems to be a new and 

 distinct form. It belongs to the British Museum. 



Cingula substriata (Philippi). Plate LI, fig. 45. 



1844. Bissoa substriata, Philippi, Enum. Moll. Sic, vol. ii, p. 132, pi. xxiii, fig. 20. 

 1873. Bissoa (Cingula) substriata, Weinkauff, Cat. europ. Meeresconch., p. 20, no. 330, 



