The accordance between this shell and the celebrated Cedo nulli of Lyonet’s cabinet, which, as before intimated, was estimated at the value of three hundred guineas, will not escape the remark those who are acquainted with the description of Lyonet’s shell. According to Favanne there were two or more varieties of the Cedo nulli, in his time, in France, that bore a very near resemblance to the shell of Lyonet; he speaks of one in the cabinet of Madame La Presidente de Bandeville, which differed in its marbling of white: in being larger and more prolonged upon the top of the first whorl, ather larger, and interrupted with veins of orange, and the last of the two belts of white spots which follows this zone near the bottom of the first whorl, composed of rather larger spots; with these exceptions the two shells were precisely the same. The Cedo nulli of Lyonet is described as being of a yellowish colour, divided into bands, the lower one and that in the middle marbled with white, the other two marked, the one with four little belts with white dots, the second with only three[3]. I ought not to close these remarks without observing, that these shells vary so considerably that no two specimens have yet occurred that agree precisely with each other. Some approach also, but are clouded instead of banded; these are the French Cedo nulli graphique, Conus mappa of Solander, and being held in less esteem from having their colours disposed in clouds instead of bands, have obtained the name of the false Cedo nulli. The transitions of these shells, it must be confessed are so various as to render it extremely difficult, if not unsafe, to determine where one species ends and another commences, the difference in the colours affords no sufficient data, neither is the form of the shell, nor the height of the spire so uniformly certain as to constitute a precise criterion. Linnæus, in his description of the conchological cabinet of her majesty _Ludovica Ulrica_, the Queen of Sweden*, speaks of three different varieties of Conus Ammiralis α _Ammiralis summus_, β _Ammiralis ordinarius_, γ _Ammiralis occidentalis_, and these are again recited in his Systema Natura. But it will be seen from the last edition of that work, by Professor Gmelin, that the varieties discovered subsequently to the age of that inestimable naturalist are very considerable, amounting to no less than thirty different kinds, and these do not include the whole at present known. Gmelin, it should be added, admits only two or three kinds as the true CEDO NULLI, which he characterizes essentially as being encompassed with dotted articulated belts, Cedo nulli cingulis punctato-articulatis; one he describes as being yellow, painted with red, and marked with eleven distinct belts of milk white; another, orange with crouded elevated interrupted chesnut lines.