290 CYLICHNA. 



Reg. Arct. Norv., p. 283, pi. 17, f. 12; pi. 11, f. 4. BUQ. DAIT/, 

 &DOLLF., Moll. Rouss. i, p. 521, pi. 64, f. 1-3. WATSON, Chal- 

 lenger Gastrop., p. 663. MOBIUS, in Die Zweite Deutsche Nord- 

 polarfahrt, 1869-70, (Koldwey), ii, p, 250, pi. 1, f. 4-9 (digestive 

 tract and dentition).- SMITH, P. Z. S. 1871, p. 738; P. Z. S. 1890, 

 ,, -J97. A. AD. in Sowb., Thes.iii, p. 590, pi. 125, f. 132. FORBES 

 A- HANI.KY, Hist. Brit. Moll, iii, p. 508. Hullo, oliwi GMEL., Syst, 

 Nat. (xiii), p. 3433. Ji. cylih<1ric BRUG., Encycl. Meth., p. 37 not 

 of Gmelin. li.producta BROWN, Illustr. Conch., pi. 19, f. 15, 16. 

 /;. nnn-oluta BROCCHI, Conch, foss. Subapp., p. 277, pi. 1, f. 7. 

 & \, HI. Catal. Conch. Req. Neap., p. 10, 1836. Cylindrella alba 

 , Malacol. p. 326, fig. 94b. 



The cylindrical form and for the group large size of this species 

 readil v distinguish it from ether European forms. The literature of 

 the species is extensive, and only the more important references are 

 given above. For others see Moll. Roussillon, Forbes and Hanley, 

 and the Challenger Report. 



Yar. LINEARIS Jeffr. Shorter, nearly smooth and decidedly 

 glossy, marked at each end with yellowish-brown spiral lines, few 

 and remote at the top, close-set at the bottom. Apex invariably 

 perforated and showing part of the internal spire. 



England; St. Helena. 



C. eylindracea has been reported from Bombay by Melvill and Aber- 

 crombie. 



C. ALBA Brown. PI. 60, fig. 16. 



SheU oblong, somewhat cylindrical, tapering toward both ends. 

 White, covered with a pellucid butt' cuticle; polished; surface 

 >ru]j,turl by extremely close, fine, superficial spiral striit, visible 

 only under a strong lens, on fresh specimens. Aperture narrow 

 above, dilated below, wider than in C. cyRndracea ; the lip curved 

 a- in that species. Columella thick but hardly folded. Apex im- 

 perforate, somewhat concave, bounded by a keel. Alt. 54, diam. 2 

 mill. Tooth-formula 5,1.1.1,5. 



f yen and Greenstuff to the liny of liisray, and to Cape Cod. 



Vol BBOWH, Illu>t. Conch, <;. r.., p. :}. pi. 19, f. 43, 44. 



Cylirhnn alba LOVEN, Ofversight Vet. Akad. F.'.rh. 1846, p. 142. 

 .hi i i:.. Brit. Cmu-h. iv, p. 417, pi. 8, f. la (dentition); v, p. 223, 

 pl.'.:J,f-6; Ann. M;^ N. IL (4), x, p. 241 ; (4), xix, p. 333 ; (4) 



