26 PLIOCENE MOLLUSCA. 



Genus POMATIAS,i Studer, 1789. 

 Pomatias Harmeri, Kennard. Plate I, fig. 9. 



1909. Pomatias Harmeri, Kennard, Proc. Malac. Soc, vol. viii, p. 316. 



Specific Characters. — Shell conical, somewhat solid, with numerous close-set 

 spiral ridges; periphery rounded; whorls 4^, rapidly enlarging, the last very tumid; 

 spire produced ; apex obtuse and smooth ; suture very deep ; mouth circular, 

 slightly angulated above; umbilicus narrow; operculum unknown (Kennard). 



Dimensions. — L. 10 mm. B. 8 mm. 



Distribution. — Not knowni living. 



Fossil : Waltonian Crag : Little Oakley. 



Remarks. — The shell now figured is a unique specimen from Oakley. It differs 

 from the Recent British species P. elegans, and I was unable to discover anything 

 else to which it could be referred. Submitting it to Mr. Kennard he expressed 

 the opinion that it was new to science, and proposed to describe it under the name 

 here adopted. I thank him for the friendly compliment. 



Comparing the present specimen with P. elegans he says the sculpture of that 

 species is reticulate, as in neai-ly all the European forms of Pomatias, the spiral 

 ridges being connected by numerous longitudinal strise. In P. Harmeri the ridges 

 are coarser, and the intersecting strige are absent ; in form the shell is distinctly 

 broader in proportion to its height. 



He further remarks that he is unable to identify it with any of the eleven recent 

 species of Pomatias [Cijclostoma) cited by Westerlund from the Palfearctic region, 

 and that there is no extinct form known to him with which it compares. He points 

 out, moreover, that the discovery of this shell at Oakley greatly extends the age of 

 the genus Pomatias in England, as it had not previously been recorded from any 

 deposit older than the Pleistocene. P. elegans occurs fossil at many localities in 

 our Holocene and Pleistocene deposits, as for example at Barrington, Ightham 

 and the Happaway cavern in Devonshire ; it is a Recent British form, with an 

 exclusively southern range. 



1 These shells have been known from the time of Draparnaud (1801) to the present, under the generic 

 name of Cijclostoma, as for example to H. and A. Adams, Clieuu and Fischer, as well as to the Couclio- 

 logical Society of G-reat Britain. Recently, however, on grounds of priority, Messrs. B. B. Woodward 

 and Kennard have revived Studer's term Pomatias (1789), which had been lost sight of for more than 

 100 years, and had been applied by Hartmaun (1821) to a different group of MoUusca. It seems an 

 open question, however, whether under the circumstances the use of a name so long established and so 

 widely known might not have been retained. 



