ACME. 205 



RossMASSL. Iconog. pt. .5, p. 54, pi. 28, f. 408. — Potiez, 

 and Mich. Gal. Douai, Moll. vol. i. p. 199 (animal). — 

 Gras, Moll. Ter. et FIuv. France, p. 54, pi. 4, f. 24. 

 ('i/dosloma lineatum, Ferus. Diet. CI. Hist. Nat. vol. ii. p. 90. 

 ^Icmc lincata, Hartm. in Sturm Deutsch. Fauna, sect. vi. pt. 7, pi. 2. — Alder, 

 Trans. Nat. Hist. Soc. Northumb. and Durh. vol. ii. p. 33o; 

 Cat. Moll Northumb. and Durh. p. 41. 

 Curijchtnm fuscum, Fleming, Brit. Anim. p. 270. — Jeffreys, Trans. Linn. 



Soc. vol. xvi. p. 364, 517. 

 Bidimus Uneatus, Turt. Manual L. and F. W. Shells, p. 83, f. 66. 

 Acmefusca, Gray, Manual L. and F. W. Shells, p. 223, pi. 6, f. GG.— Thomp- 

 son, Ann. Nat. Hist. vol. vi. p. 11 ?• — Brown, Illust. Conch. 

 G. B. p. 34, pi. 18*, f. 28. 

 „ minuta. Brown, 111. Conch. G. B. p. 35, pi. 14, f. 26? 



Shell minute, narrow, the length being to the breadth 

 as three to one, cylindrical, but tapering convexly above 

 to a rounded apex, of an uniform highly polished clear 

 transparent brownish amber colour, striated throughout by 

 distant longitudinal scratchlike lines. V/horls six, deeply 

 divided by a moderately slanting suture, near which they 

 are decidedly convex, though not much rounded in the 

 middle, of only moderate longitudinal increase ; the penult 

 and antepenult turns rather long ; body short, its basal 

 declination rather abruptly rounded. Mouth only filling 

 about a fourth of the total length ; much contracted 

 above, bluntly rounded below, of a rhombic-ovate shape, 

 the pillar distinctly forming an obtuse angle with the 

 parietal or upper portion of the inner lip. Outer lip 

 simple, acute, not prominent, straightish above, rather 

 suddenly arcuated below. Pillar lip nearly straight, 

 rather long, a little reflected over the umbilical crevice. 



The operculum was first noticed, we believe, by the 

 Abbe Dupuy. It is very fugacious, horny, exceedingly 

 thin, oval in outline, transparent, and subspiral. 



Length of shell only a tenth of an inch. 



Animal varying in colour from white to dark brown. 



