72 AMERICAN MARINE CONCHOLOGY. 
gular above, widely rounded below, slightly effuse. Lip sharp, 
modified by the revolving lines; the canal, an oblique fissure. 
Operculum horny, ovate, concave externally, multispiral. Bluish 
to reddish-black. 
Length 5, diam. 2.5 mill. 
Cape Cod, Mass., to North Carolina. 
2. B. GreEentI, Adams. Fig. 128. 
(Cerithium) Bost. Journ. Nat. Hist., ii. 287, t. 4, f 12. 1839. 
? Cerithiopsis tubercularis, Mont. (sp.) 1803, teste Jeffreys. 
Shell very small, cylindrical ; beneath deeply rugose, with lon- 
gitudinal ridges and revolving lines. Canal very deep and short, 
slightly curved. Aperture one-eighth the length of the shell, nearly 
circular. Reddish-brown. 
Length 5, diam. 1.25 mill. 
Mass. to North Carolina (Hur.). 
Genus TRIPHORIS, Deshayes. 
Animal. The tentacles are clavate at the tips, united at their 
bases by a sinuated veil. 
The species are very numerous, inhabiting all seas, but princi- 
pally tropical. The sculpture of the whorls is very varied, beauti- 
ful, and constant. 
1. T. niGRooINcTUS, Adams. Fig. 129. 
(Cerithium) Bost. Journ. Nat. Hist., ii. 286, t. 4, f. 11. 1839. 
Shell conic-cylindrical, with three revolving series of granules. 
Whorls reversed, suture broad, carinate; aperture small, subellip- 
tical, ending in a twisted canal about one-third as long as the 
aperture. Reddish-black; columella black; a black spiral belt 
in faded shells. 
Length 7.5, diam. 1.75. 
Massachusetts to North Carolina. 
Family V. TURRITELLIDA. 
Synopsis of Genera. 
Shell elongated, many-whorled, spirally striated ; aperture rounded, mar- 
gin thin ; operculum horny, many-whorled. TurrrrELLA, Lamarck. 
Shell tubular, attached ; sometimes regularly spiral when young; always 
irregular in its adult growth; tube repeatedly partitioned off; aperture 
round ; operculum circular, concave externally. VERMETUS, Adanson. 
