History of British animals - University of Guam Marine Laboratory

Trochus. MOLLUSCA. TROCHUSID^E.T. lineatus (Da Costa, Brit. Conch. 100. t. vi. f. 7-), Don. Brit. Shells,t. 71—T. crassus, Mont. Test. Brit. 281 English coast, on rocksabout mid tide.Length and breadth about an inch ; purplish-brown, with numerous whitezigzag lines ; shell strong, whorls coarse and wrinkled by the lines ofgrowth base convex ; ; aperture rounded ; pillar lip concave in the middle,in front of which is the tooth. According to!;Montagu there is a sort of plumebehind the left eye, composed of simple contiguous fibres.- 286. T. papittosus.— Whorls eight, flat, with numerous spiraltuberculated ridges and striae.{Da Costa, Brit. Conch, p. 38. No. 20. t. iii. f. 3.) Don. Brit. Shells,t. cxxvii—T. tenuis, Mont. Test. Brit. 275. t. x. f. 3.—South coastsof England and Ireland.Length l|th inch, breadth rather less ; pale reddish-brown, with red spots ;whorls scarcely distinguished by the separating line ; the tubercles on theridges are transverse, smooth, the intervening strife are slightly decussatedby the lines of growth ; base with numerous, spiral grooves, finely striatedacross by the lines of growth ; aperture slightly angular ; pillar-lip concave.- 287- T. ziziphinus.— Whorls eight, flat, separated by asmooth circular ridge, obsoletelystriated spirally.T. albidus, List. An. Ang. 166. t. iii. f. 14. Conch, t. Dcxvi. f. 1.T. ziz. Linn. Syst. 1231. Mont. Test. Brit. 274 Not uncommon,near low water mark.Length and breadth about an inch ; livid, the separating ridge with darkerand lighter coloured spaces ; spire conical, pointed base ; smooth, spiraDystriated with diverging curved lines of growth ; aperture quadrangular ;the pillar-lip slightly concave, with an obsolete tooth at the anteal extremity—Awhite variety of this shell was sent me several years ao-o bv DrLeach, with the name T. Lt/onsii, from Tenby.-288. T. exasperatus.— Whorls seven, flat, separated by atuberculated circular ridge.T. pyramidalis parvus, List. Conch, t. Dcxvi. f. 2 T. exasp. Penn.Brit. Zool. iv. 126—T. conulus, Don. Brit. Shells, t. viii. f. 2.— T.exiguus, Mont. Test. Brit. 277—Southern coasts, rare.Length |ths of an inch, breadth |ths; crimson-red, with white spots ;whorls with four smaller slightly tuberculated spiral ridges, the interveningspaces pitted base with ; nearly smooth spiral striae, slightly convex wherethe body-whorl enters the aperture.•289- T. striatus. — Whorls seven, flat, with an indistinctseparating ridge, smooth on its upper surface.Linn. Syst.i. 1230. Pull. Dorset, p. 44. Mont. Test. Brit. 278 T.conicus, Don. Brit. Shells, t. civ. f. 1—T. erythroleucos, Turt. Conch.Diet. 191—On the southern coasts.Length |ths of an inch, breadth jjths ;grey, with transverse waved blacklines ; spiral stria?, on the base and surface of the whorls, numerous, crossedby sharp oblique lines of growth, which extend across the outer edge of theseparating ridge; base flat, the body-whorl, where entering the aperture,slightly concave ;aperture angulated.X2