TRUNCATELLINA. 



77 



Pupa batiagliensis DE GREG., Ann. de Geologic et de Pale- 

 itologie, 32 livr., 1907, p. 13, pi. 1, f. 30. 



11. TRUNCATELLINA RIVIERANA BRITTANICA n. subsp. PL 8, 



figs. 13, 14. 



The minute shell is shortly, deeply rimate, imperforate, 

 Iric in the last three whorls, those above forming an 

 >tuse dome; cinnamon colored; glossy; evenly but not 

 tarply rib-striate, the riblets oblique, about 2 in 0.1 mm. on 

 ic last whorl ; first 1% whorls smoothish, pale. The whorls 

 strongly convex, the last not flattened laterally towards 

 ie base, without any trace of a crest behind the lip. The 

 iperture is ovate. Peristome paler than the shell, well thick- 

 icd, but narrowly expanded. On the parietal wall there is 

 short tooth, so deep within that it is not seen in a direct 

 ice view. The columella has a strong but obtuse tooth, visible 

 an oblique view in the aperture. In the palate an im- 

 ;rsed, rounded or oblong tubercle, visible in a direct front 

 lew. 



Length 1.74, diam. 0.85 mm. ; 5% whorls. Type. 

 Length 1.65, diam. 0.83 mm. ; nearly 5% whorls. 

 England: Portland, Dorset, with T. cylindrica (G. C. 

 >pence) ; type and paratypes no. 109423 A. N. S. P. 

 It resembles T. rivierana of southern Europe, but in that 

 jcies the parietal lamella and the palatal fold are longer 

 id stronger and the striae more spaced. T. odontostoma is, 

 wording to Westerlund, a larger and relatively longer shell, 

 mm. long, % mm. wide, with 6-7 whorls and a thin peri- 

 >me. If Westerlund 's account is correct, the position of the 

 latal fold is different. Unfortunately, Westerlund 's form 

 not been figured, and no other author has reviewed its 

 iracters and dimensions. 

 While it appears unlikely that this British form is without 

 name, I cannot find any applicable to it. By formally de- 

 bribing the shell, the attention of British conchologists will 

 called to it, and a more thorough investigation can be made 

 lan is possible from this side of the Atlantic. Various early 

 >wiss species might be compared if anybody could tell what 

 leir characters are. 



