CHEMNITZIA. 415 



laria basi coalita, lateribus raembranaceis, apicibus lobis minutis, 

 aut simulantibus, instructis. Oculi, ad basin centralem vel in- 

 ternam tentaculorum immersi. Pes characterem nullum constan- 

 tem exhibens. 



Testa spiralis, laevis, vel costata, vel lineis spirata, aut decussata, 

 anfractibus tribus ad octodecim instracta ; apertura ecanaliculata ; 

 latus columnare denticulo saepe munitum, ssepe muticum. Apex, 

 in gyrum sequentem reflexus. Operculum corneum, vel subtes- 

 taceum, subovale, striis ellipticis notatum, subspiratum, aref. 

 inferior! sub nucleo, apophysi semper instructa. 



C. PALLIDA, Mont, certe. 



Odostomia eulimoides, Brit. MoU. iii. p. 272, pi. 95. f. 1, 2, 3. 



O. ? pallida, Brit. MoU. iii. p. 307, pi. 98. fig. 4, and iv. p. 274. 



O. notata, O. albella, O. dubia, O. alba, O. nitida, O. rissoides, 



O. eulimoides, O. glabrata, auct. variorum*. 

 O. dubia, Brit. MoU. iii. p. 276, pi. 94. f. 8, and iv. p. 279. 

 O. alba, Brit. MoU. iii. p. 278, pi. 96. f. 9. 

 O. nitida, Brit. MoU. iii. p. 280, pi. 94. f. 6. 

 O. glabrata, Brit. MoU. iii. p. 283, pi. 98. f. 3. 

 O. rissoides, Brit. MoU. iii. p. 284, pi. 96. f. 4 (5, var. albella), and iv. 



p. 279. 



Animal of six spiral turns ; mantle plain. Foot short, trun- 

 cate in front, slightly aurieled, but not emarginate or hollowed 

 out in the centre, as in its congener below, Chemnitzia acuta -, 

 rounded posteriorly, and terminating suddenly in a short 

 point; it is powdered on its upper surface with pale gold- 

 coloured minute points, and in some specimens with sulphur- 

 yellow dots ; beneath the same colours prevail, though less 

 intensely : it has a light corneous, simple, not spiral, suboval 

 operculum. The organ above the foot, and under the tenta- 

 cula, termed by us the rostrum, and by others the mentum, is 

 marked on each side with a pale yellow longitudinal line ; on 

 the quiet march it is short, thick, flat, slightly bevelled at the 

 sides, truncate and dilated at the extremity ; but when the 

 animal is disturbed, it presents many phases of figure, which, 

 without great care, may occasion discrepancies in the de- 



* Figures of most of these varieties may be seen in that valuable vade 

 mecum, the * British Mollusca.' 



