DENTALIUM. 101 



cylindrical, numerously ribbed at the apex, with additional striae 

 afterwards, with a tendency to become smooth near the margin. 

 In the next species, B. dentate, this tendency is not observable. 



26. D. dentale, Linn., f. 14. — Testa elongata, acuminata, J2- 

 costata, interstriata, pallide rosea, transverse rubro-fasciata, apice 

 integro^ — More distinctly ribbed than B. Lessoni, without the 

 same tendency to become smooth towards the margin. It is 

 banded with red. 



27. D. Belcheri, Sowb. Jim., f. 28, 29. — Testa subcylindracea, 

 secjualiter crebri-costata, versus apicem leviter arcuata, alba vel 

 rosea, ad costas pallide maculata, ; apice integro, obtuso. — It is 

 like B. novetn-costatum, but with the ribs much more numerous. 

 There is a slight articulated appearance on the costas. 



28. D. cancellatum, Sowb. Jim., f. 36. — Testa tenui, alba, 

 acuminata, versus apicem valide arcuata, costis circiter 8 longi- 

 tudinalibus et striis elevatis concentricis cancellata, deinde costis 

 numerosis, testa rectiuscula. — Cancellated near the apical end by 

 distinctly raised striae crossing the longitudinal ribs. 



29. D. liratum, Carpenter, f. 32. — Testa alba, parva, recta, 

 cylindracea ; costis longitudinalibus, sequalibus, circiter duodecim. 

 — A very small, white, straight, narrow, 12-striated shell. 



30. D. variabile, Besh., f. 30. — Testa alba, cylindracea, an- 

 gusta, prope apicem leviter arcuata ; costis insequalibus, plerumque 

 versus apicem paucis, deinde magis numerosis, plerumque quasi 

 articulatis ; apice integro. — The ribs are usually few near the 

 apex, but at various lengths their number is increased by inter- 

 mediate ones, so as, in some specimens, to become numerous and 

 equal. They are spotted or articulated. It is much more narrow 

 and cylindrical than B. Belcheri. 



31. D. zelandicum, Sowb. Jim., f. 13. — Testa alba, pallide 

 griseo et fulvo fasciata, vix arcuata, pyramidali, lata ; costis nume- 

 rosis, paululum elevatis, insequalibus ; apice vix fissurato. — Very 

 similar to B. rectum, but the sculpture far less bold and coarse. 



32. D. rectum, Gmel., f. 1. — Testa crassa, magna, retrorsum 

 subarcuata, pallida, pyramidali, subacuminata, ad apcrturam lata; 

 costis numerosis, valde ina;qualibus ; fissura apicali elongata. — 

 This is figured and described by Deshayes, as B. elephantimun of 

 Linnaeus, with which it by no means agrees. It is coarsely and 

 unevenly ribbed, and has a backward curve in the centre, from 

 thence bending forward at the apex. 



33. D. Vernedei, Hartley, f. 3. — Testa magna, alba, pallide 



