longitudinally, often smoother; aperture large, inner 
margin ridged transversely; operculum quadrivalve, 
not striated, angulated, erect. Dorset, §c. Diam. 0,40. 
B. Scoticus.—Lepas 8. Wood. G. C. t. 6. f.3. p. 
10.—Turt. D. p. 76.—Conical, with six valves, dirty 
white ; valves longitudinally ribbed, unequal, striated 
transversely at the base. #%.. 2. Scotland on My- 
tilus modiolus, Lin.—This brief description is all that 
as given by Mr. Wood, saving that he farther states 
that the operculum resembles that of Tintinnabulum, 
I regard it as of rather doubtful distinctness. 
B. Punctatus. Dor. Cat. p. 25. t.1. f. 10. (not 
Lam: nor Brug.)—Mont. p.8.t. 1. f. 5—Lepas P: 
Wood. G. C. p. 46.—D: p. 15.— A. Turt. D. p.78.— 
An L. CornnvuBiEns!s: Pen. 4.p. 73. t. 37. 7.6. ?— 
An B. Crenatus? Brug. p. 168.—Very rugged, 
brown, valves indistinct, usually punctured, base 
spreading but little and scarcely broader than high ; 
anterior valve always provided with two connecting 
shoulders; operculum of four valves, the upper one with 
a few longitudinal ridges, (the edges of the superior and 
anterior valves generally closely united at the top, 
indented or notched, punctated and _ interlocking. 
S. Devon, common on Patella Vulgata. 
B. Costatus: Mont. p. 11.—Lrpas C. Don. t. 30. 
