DKNTALIUM.— Plati: V. 



Species 42. (Mus. Brit.) 

 Dentalium cuktu.m. Den. testa brevi, jmllide fah-d, 



tenniter striata, valicle arcuatd, rapidu crescenti ; 



iijiice attenuato et acuminata ; Jissurd apicali 



parvo. 

 The shout Dentaliuii. Sliell short, pale brown, 



finely striated, strongly arched, rapidly increasing; 



apex attenuated and acuminated ; apical fissure 



small. 

 SowEUBY. Thesaurus Conchyliurum, Dentaliiim, Sp. 

 2;i, f. 64. 



Species 43. (Mus. Brit.) 



Dkntalium aculeatum. Z>eii. tesld alba, validissimi- 

 arcuatd, rapide crescenti, inoBqualiter striata, versus 

 apicem attemiatd, acuminata, versus marginem lata ; 

 aplce intcr/ro. 



The Aci'LEATED Dektalium. Shell white, very strongly 

 curved, rapidly increasing, uneipially striated, at- 

 tenuated and acuminated towards the apex, broad 

 Inwards the margin; apex entire. 



SowERBv. Thesaurus Conchyliurum, Dentalium, Sp. 22, 



f. G;!. 

 Ilab. ? 



Too much curved and unequally striated to be the 

 young of Dentalium Tarentinum. 



Species 44. (Mus. Hanley.) 

 Dentalium ustuea. Den. testa recta, ungustissimd, 



ci/lindricd, alhd, politissiind ; apice integro. 

 The pipe Dentalium. Shell straight, very narrow, 



cylindrical, white, very polished ; apex entire. 

 SowERBY. Thesaurus Conchyliorum, Dentalium, Sp. 15, 



Hub. ? 



The fossil named Dentalium Duplex hy Deshayes, re- 

 sembles this, but there are no specific characters by 

 which to identify it. The double termination or sepa- 

 ration of the outer from the inner wall of the tube at 

 the apex, from which the species of Deshayes derives 

 its name, is not inireijuent in many species. 



