If in the preceding instances we have produced some novelties worthy of particular attention, the present shell, in point of value as well as beauty, must also lay a distinguished claim to our consideration. This is one of those rare varieties of Conus Ammiralis denominated the CEDO NULLI, or CEDO NULLI _pretiossissimus_, in allusion to the incomparable value affixed to the varieties of this peculiar species. The importance attached to the shells of this kind may indeed be best conceived by stating that some of its varieties have been valued at twenty, fifty, and one hundred guineas; one, in almost every respect resembling that delineated at figure 4, the celebrated Cedo Nulli of Lyonet’s cabinet, was valued by Lyonet himself, about the year 1732, at three hundred guineas; and either this shell, or another very similar to it, actually realized a sum of 1200 florins. As the shells of this kind may very justly be presumed to be of the first rarity, every trait of information that may appear calculated to elucidate their history, it is presumed, will not only be permitted but be deemed acceptable, and under this impression the ensuing observations are submitted. Much about the æra of the first explosion of the French Revolution of 1789, and within the space of a few years after, it is perfectly well known that many of the choicest cabinets and collections of rarities that had before been the pride of France and Holland were consigned to this country for the sake of safety, and being in some instances afterwards dispersed, had tended, in no small degree, to enrich the cabinets of our own country. It was at this period that many very rare shells occurred to our observation which have since disappeared, and among others, several of those varieties of Cedo nulli which had been before held in other parts of Europe in considerable estimation. In the year 1797 we saw no less than five specimens of this rare shell, all varying a little from each other, in the cabinet of the French Minister of State, M. de Calonne; in one, the colour was pale, in another deeper, one was lineated, and another distinguished by having three distinct bands. At the dispersion of the Calonnian Museum, which took place by public sale rather more than twenty years ago, the series of these valuable shells passed into the fine collection of the present Earl Tankerville, a collection his lordship was then forming for the pleasure of an amiable and beloved daughter since deceased, and these shells are still considered among the more choice rarities of that valuable cabinet.