DENTALIUM-ANTALIS. 43 



jagged, owing to that part of the shell being nearly formed and con- 

 sequently much thinner than other parts; at the posterior or nar- 

 rower end it is usually truncated in adult specimens, and furnished 

 with a very short sloping and oblique pipe or tubular appendage 

 having a pear-shaped orifice ; there is also occasionally at the point 

 on the convex side a notch or groove, in a line with the front or 

 smaller part of the tubular appendage, and this notch is rarely ex- 

 tended into a short and narrow slit or channel. (Jeffreys). 



Length 37-42, diam. of aperture 4'5-5 mill. 



Spitzbergen, Scandinavia, Iceland, and Atlantic coasts of Europe, 

 south to Spain., 3-1750 fins. Coasts of Maine and Massachusetts, 

 north to Bay of Fundy. 



D. entails LINN., Syst. Nat. (10), p. 785 ; (12), p. 1263. PENN- 

 ANT, Brit. Zool., iv, p. 145, pi. 90, f. 154 (1777). LAMARCK, An.s. 

 Vert., v, p. 345 (1818). FORBES & HANLEY, Nat. Hist. Brit. Moll, 

 ii, p. 449, pi. 57, f. 11 (1853). HANLEY, Ipsa Linn. Conch., p. 437, 

 548 (1855). REEVE, Conch. Syst., ii, p. 6, pi. 130, f. 3 (1842). 

 JEFFREYS, Brit. Conch., iii, p. 191, pi. 5, f. 1 ; v, pi. 55, f. 1 (1865) ; 

 P. Z. S., 1882, p. 659. WATSON, Challenger Scaph. & Gastr., p. 5 

 (1885). D. entale L., and D. antale of some authors. Not D. en- 

 talis or D. entale of writers on Mediterranean shells, or of Searles 

 Wood and some other palaeontologists. D. entalum DE BLAINV., 

 Diet. Sc. Nat., xiii, p. 70. 



D. striolatum STIMPSON, Proc. Bost. Soc. Nat. Hist., iv, p. 114 

 (1851); Shells of New England, p. 28 (1851). Entalis striolata 

 Stimp., GOULD-BINNEY, Invert, of Mass., p. 266, f. 528 (1870). 

 Not D. striolatum of Jeffreys, Watson or Sars. Not D. striolatum 

 Risso, 1826. 



More glossy and ivory-like than D. vulgare, usually more dis- 

 tinctly annulated, and with the longitudinal striae completely want- 

 ing except at the smaller end, where their presence is variable. The 

 posterior termination has either a labial projection which is rather 

 broadly fissured dorsally (i. e. upon the arched side of the tube) or 

 if it have not experienced that reparative process is then very taper- 

 ing, and has a short shelving notch-like dorsal fissure; it is always 

 entire upon the ventral or incurved side of the shell. In certain 

 specimens the close approximation of the concentric lines of growth 

 produces a somewhat annulated appearance. (F. & jET.). 



D. entails is an abundant species on the coast of Maine; and 

 William Stimpson, comparing with the European D. vulgare and 

 finding differences, distinguished the American shells as D. striolatum, 



