118 DENTALIUM-EPISIPHON. 



D. sowerbyi GUILDING, Trans. Linn. Soc. Lond., xvii, p. 35, pi. 

 3, f. 7 (1834). 



Known only by Guilding's description and figure. 



The relation of this form to D. fistula and D.filum requires in- 

 vestigation ; but as only the last named of these species is known to 

 us by specimens, we deem it best to present the information upon 

 all three, unprejudiced by an attempt at synonymy. 



D. FISTULA Sowerby. PL 18, fig. 4. 



Shell subhyaline, narrow, nearly straight, the apex entire. 

 (Sowb.). Length 21 mill, (from figure). 



Habitat unknown (Hanley coll.). 



D. fistula Sows., Thes. Conch., iii, p. 99, pi. 225, f. 62, under f. 

 45 (1860). 



Mr. Sowerby seems to consider this doubtfully distinct from D. 

 duplex Defr., of the Paris Basin Eocene, but in that species the tube 

 is compressed and provided with two internal ribs. Deshayes in his 

 MS. catalogue places fistula under D. sowerbyi Guilding. We have 

 seen no specimen. 



D. FILUM Sowerby. PI. 18, fig. 9. 



Shell extremely narrow and slender, gently curved, thin, nearly 

 transparent and glossy. Sculpture : slight concentric lines of 

 growth, which are scarcely perceptible ; color clear white. Aper- 

 ture circular ; margin at the anterior end more or less jagged, owing 

 to its excessive tenuity and fragility ; at the posterior end truncated, 

 with an internal pipe (in adult shells) and slightly notched ; in 

 the fry this latter part has a pear-shaped and perforated point. 

 Length 12?, breadth li mill. 



Mediterranean, from the ^Egean (off Crete 70-250 fms., Spratt), 

 and Algeria to Gibraltar (MacAudrew) ; E. Atlantic, Vigo (Mac 

 Andrew) ; Bay of Biscay (Travailleur). Off North Carolina coast 

 17-124 fms. (U. S. Fish Comm.) ; older Miocene of the Chipola 

 Beds, Calhoun Co., Florida (Burns) ; Pliocene of Calabria 

 (Seguenza). 



Dentalium sp. ined., very slender, MACANDREW, Rep. Mar. Test. 

 Moll. N.-E. Atl., in Rep. Brit. Asso. Adv. Sci. for 1856, p. 117. 

 D. filum SOWERBY, Thes. Conch., iii, p. 89, pi. 225, f. 45, Gibraltar 

 specimens only, (1860); Conch. Icon., pi. 5, f. 31 (not fig. 32). 

 JEFFREYS, P. Z. S., 1882, p. 660. HIDALGO, Catal.Moll.Espagne, 



