132 ENTALINA. 



With the shell of Dentalium, this group combines the form of foot 

 of Pulsellum. It differs from all other Siphonodentaliidce in the 

 strong sculpture of the shell ; and in a group otherwise so constantly 

 characterized by smooth, rounded shells, this strongly angular ex- 

 terior is apparently as important as anything. Even though Cadu- 

 lus, Siphonodentalium and their satellite groups be merged into one 

 genus, we would still segregate Entalina. 



E. QUINQUANGULARIS (Forbes). PI. 24, figs. 30, 33, 34, 35, 36, 37, 



38. 



Shell small, slender, evenly and considerably tapering from base 

 to apex, the apical half strongly curved, larger half of the tube 

 nearly straight. Very faintly buff tinted, bluish-white in places ; 

 lusterless. Sculpture : at and near the apex five-sided and five- 

 angled, the angle along the incurved side obtuse, the others nearly 

 right angles ; spaces between the angles flat, gradually becoming 

 convex as the tube enlarges, the angles at the same time becoming 

 weaker and then obsolete, so that the later third of the shell is cylin- 

 drical; between the angles several cord-like riblets appear a short 

 distance from the apex, and continue to the aperture, where they 

 number about 28 or 30. Aperture quite oblique, circular in adult 

 shells ; apex minute, the orifice with simple edge or variously irreg- 

 ularly chipped or nicked by breakage. Length 12-13, diam. at 

 aperture T5 mill. 



Lofoten, Norway to Spain ; Mediterranean, east to the JEgean, 5 to 

 650 fms. ; Pliocene of S. Italy and Sicily. 



Dentalium quinquangulare FORBES, Rep. JEgean Invert., in Rep. 

 Brit. Asso. Adv. Science for 1843, p. 188 (1844). SOWERBY, Thes. 

 Conch., iii, p. 103, pi. 224, f. 33 (I860). Siphonodentalium quin- 

 quangulare Forbes, JEFFREYS, Ann. Mag. Nat. Hist. (3), xx, p. 

 251 (1867) ; (Series 4), v, p. 442, and vi, p. 74 (1870). WEIN- 

 KAUFF, Conch, des Mittelm., ii,p. 421 (1868). ARADAS & BENOIT, 

 Conch. Viv. Mar. Sicil., p. 118 (1870). LOCARD, Prodr. Mai. Fr., 

 in Ann. Soc. d'Agricult. Lyon, (5), ix, 1886, p. 149. DAUTZEN- 

 BERG, Mem. Soc. Zool. France, iv, p. 609. Siphodentalium quin- 

 quangulare Forbes, JEFFREYS ? P. Z. S.. 1882, p. 663. Siphonentalis 

 quinquangularis Jeffr. CARUS, Prodr. Faun. Medit., p. 176. Enta- 

 lina quinquangulare Forbes, MONTS., Nomencl. Gen. e Spec. Conch. 

 Medit., p. 33 (1884). 



