100 LITTORINlDiE. 



commencement of ^Yllose basal declination (often indicated 

 by a raised spiral interstitial stria) they become obsolete. 

 The Avhorls, which are well defined by a very fine suture, 

 are six or seven in number ; they are not ventricose, but 

 only moderately convex or even somewhat flattened. 

 Their longitudinal increase is gradual, and, for the most 

 part, they are rather short than otherwise. The spire, 

 which, in general, scarcely exceeds the body in length, 

 though occasionally it Is more produced, ends in a small 

 but not very acute point, that is sometimes whitish, some- 

 times tinged with purple. The basal slope of the body- 

 whorl is rather gradual, and more or less flattened. The 

 mouth, which occupies t«vo-fifths of the entire length, is 

 roundish oval, a little contracted above, and broadly ar- 

 cuated below, where it is slightly disposed to expand. The 

 peristome is continuous, and in typical examples is wholly 

 or partially edged with brown or cinnamon colour; it is 

 rather broadly reflected over the pillar. The outer lip is 

 arcuated both above, and, more especially, below, where it 

 is apt occasionally to form an angle with the pillar lip ; it 

 is thickened externally by a broad and solid varix-like 

 rib, on the upper part of which is painted a curved and 

 oblique linear streak of brown, whilst the termination of 

 a revolving basal line of the same tint is likewise visible 

 near its lower extremity. Two lines is the full length 

 of individuals ; their breadth is rather more than half 

 this measurement. 



Turbo iiitcrruptiis, Adams, Trans. Linn. Soc. vol. v. pi. 1, f. IG, 17 (probaljly). 



— MoNT.Test. Brit. p. 329 ; Suj^pl. pi. 20, f. «. — Donov. 

 Brit. Shells, vol. v. pi. 178, f. 2. — Maton and Rack. Trans. 

 Linn. Soc. vol. viii. p. 166. — Turt. Conch. Diction, p. 205. 



— Brit. Marine Conch, p. 182. — Dillw. Recent Shells, 

 vol. ii. p. 841.— Wood, Index Testae, pi. 31, f. 62. 



Cingula inlerriipta, Flkminc;, Brit. Animals, p. 30!). 



