_London. Published, as the Act directs, by E. Donovan, July 1, 1822._ ] ------------------------------------------------------------------------ CONCHOLOGY. PLATE XI. TROCHUS IMPERIALIS var α ROSEUS PINK, OR ROSEATE, IMPERIAL SUN TROCHUS. UNIVALVE. GENERIC CHARACTER. Shell spiral, more or less conic: aperture sub angular, or rounded, the upper side transverse and contracted: pillar placed obliquely. SPECIFIC CHARACTER AND SYNONYMS. Shell conic, olive, covered with rows of arched violet scales: whorls inflated, with a spinous radiate margin: perforation funnel-shaped and white. * Variety, pink or rose-coloured. TROCHUS IMPERIALIS: testa conica olivacea, squamis violaceis seriatis fornicatis tecta: anfractibus inflatis margine spinoso radiatis, umbilico infundibuliformi albo. _Gmel. Linn. Syst. Nat. 3576. 63._—Var OLIVACEUS. TROCHUS IMPERATOR _Chemn. T. 5. 173. 174._—Var OLIVACEUS α PINK SUN TROCHUS _Lev. Mus._ * * * * * We cannot for a moment hesitate to believe that in announcing to our readers the introduction of the Pink, or Roseate Imperial Sun Trochus: the significant appellation under which the present rarity has been for many years distinguished, we shall awaken the attention of every Conchologist and amateur of the science. The shell so named, formerly constituted an object, no less conspicuous than beautiful, among the Conchological productions treasured together in the once celebrated Leverian Museum. And, as we possessed, through the immediate favour of the proprietor of that Museum, John Parkinson, Esq. an unreserved access to every article in the Museum, for the purpose of delineating the figures, or taking the descriptions of whatever we conceived worthy of such observation, it will be naturally imagined the Pink, or Roseate Imperial Sun Trochus, would be esteemed of too much importance to escape our very particular attention. The dispersion of that once celebrated Repository of Natural History has long since removed, and probably for ever, this exquisite rarity from the eye of public curiosity; nor indeed is its present destination correctly known; a circumstance, it is presumed, that cannot fail to enhance the value of a drawing, which we have every reason for believing to be the only memorial of this kind the pencil of the Arts have consecrated to the commemoration of the shell: the only figure, we are assured, the proprietor ever permitted to be taken from it.—Having premised so far, it will not be deemed superfluous to add, that the outline of the specimen is precisely a fac-simile of