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although they were ostentatiously offered to the goddess of beauty; for Pliny, who narrates the circumstance, states at the same time that the pearls from Britain were small and lustreless, and not to be compared with those from the East. Tacitus, in his Life of Agricola, describes the pearls of Britain as 'subfusca ac liventia;' and among ancient Christian writers they are mentioned by Origen and Bede. Pennant, and other writers, who have treated of pearls, have all taken it for granted that those mentioned by the ancient authors quoted were derived from the Unio. This, however, is by no means clear, and Cæsar's buckler was more probably covered with pearls from Mytilus edulis, very much inferior in quality and size to those from the fresh-water Pearl Mussel, and agreeing better with the disparaging account of them in Pliny. Those mentioned by Camden, as occurring at the mouth of the Irt, in Cumberland, seem to have been of the same nature. The pearl-fishery at the mouth of the Conway [to which I have already referred] also concerns the Mytilus and not the Unio. Higher up the latter river, however, and in many rivers of all parts of the kingdom, especially in the neighbourhood of mountainous districts, the Unio has been at various times fished to a great extent for pearls, and, in all probability, the fame of British pearls that attracted the Roman conqueror was due to the products of the shell before us. The best account of these fisheries of the freshwater Pearl Mussel is contained in a curious paper in the seventeenth volume of the 'Philosophical Transactions,' (1693,) written by Sir Robert Redding, and communicated by Dr. Martin Lister. This paper has been often referred to by subsequent writers, who,