The Anomia genus, instead of being devised by Linnæus, or Terebratula in particular, owing its invention to any modern writer, have been both so long established that the greatest difficulty is to determine where in the retrospect of authors our enquiries are to cease. Without proceeding further back than the last two centuries, it may be observed that _Fabius Columna_ in his work “De Purpura,” published at Rome in the year 1616, speaks of the Anomiæ; he calls them _Conchæ rariores Anomiæ_, and from that period at least the term Anomia has been received among Naturalists. Nor is the term Terebratula of much later origin. Da Costa in his Elements of Conchology informs us that from the time of Fabius Columna the word Anomia had become universal, that is as a general denomination for all the shells which Linnæus subsequently placed together under that name. The term Terebratula was given, says this writer, by Gualtieri; in plate 96 of his work, Gualtieri figures three recent kinds, and has made a particular genus for them, which he calls Terebratula. And it is further added in another place “the Anomiæ are bivalves with unequal valves, and never eared, the beak of the largest or under valve is greatly produced, and rises or curves over the beak of the smaller or upper valve, and is perforated or pierced through like a tube, from which particular they have also obtained the name of _Terebratulæ_.” These remarks sufficiently establish the circumstance of the term Anomia, being a comprehensive title for all the shells which Linnæus subsequently placed together under that name, and also shews that we are not indebted to either Bruguière or Lamarck for discriminating the Terebratulæ. We can ever go further back in this particular than Da Costa has done, for that able author is mistaken in supposing Gualtieri to be the first writer who had proposed the genus Terebratula. Gualtieri published his work in the year 1724, and we happen to possess among other valuable MSS. of the celebrated Antiquarian, Hearne, the original copy of Lluid’s Lithophylacia Britannica, as corrected for the press, dated Montgomery, 1698, in which the genus Terebratula is distinctly named: and this, as it appears from the date, was more than fifty years before the time of Gualtieri; and we have also the authority of our english Lister in 1694 for the like distinction. All these writers, it will be observed, preceded Klein, who has in a particular manner described the genus Terebratula in his Methodus Ostraceologia, published in 1753, but in which he does not speak of himself as having invented that term. “TEREBRATULAS, _Luidiano_ titulo, vocamus DIACONCHAS anomalas, rostro parterebrato, vid. _Nomencl. Litholog. Promotum_ hoc titulo.” His genus _Concha_ ΤΡΊΛΟΒΟΣ, genus _Concha_ ADUNCA, genus BURSULA, and genus GLOBUS, are all sub-divisions of the _Anomiæ Conchæ_ of other writers, divided according to their forms and other