This is one among the number of those very choice accessions to the Conchological knowledge of the last century, that was derived from the scientific labours of our first circumnavigators in the Southern Ocean: it occurred to them upon the coast of New Zealand, not in any abundance, but so far plentifully that after the Banksian Cabinet was supplied there were several specimens to spare for distribution among the friends of Sir Joseph Banks, Dr. Solander, and Captain Cook. From this little store the species passed in the first instance into several collections, and among others into that of the late Duchess of Portland, Dr. Chauncey, Mr. Cracherode, Mr. G. Humphrey, and some others. It has since occurred, but not in any abundance to later voyagers in those seas. And it is reputed also to have been met with in the Straits of Magellan. The specimen of this rare shell which we have delineated, and which always was considered as one of the largest of its species known, once constituted part of the Testaceological collection of Sir Ashton Lever, having been presented to that eminent collector by Captain Cook, at the time of his return to England after his first voyage. There is a small hole pierced through the upper valve of this shell, and which, in the absence of all other information, induces the persuasion of its having been originally suspended like several other shells we have already mentioned, as an ornament or appendage to the dress of some New Zealander; the aperture being so designed that the two valves could easily have been kept together by means of a string passing through this hole of the upper valve, and the opening in the beak of the lower one. The animal inhabitant is probably eaten by the New Zealanders, who besides being cannibals, subsist chiefly upon the marine productions of their shores, which their wives and female children obtain daily for them by swimming and diving into the sea. There is a rare species found in the Mediterranean Sea, Anomia Vitrea of Gmelin, which nearly approaches this species in point of size, and is eagerly sought after, we are told, by the people of those parts as a delicious food. We should, however, imagine from its scarcity, that it is only at the tables of the rich that this luxurious repast appears. In adopting the genus Terebratula for the shell before us, some explanation may be expected for our departure from the Linnæan classification, for in the system of that author it is one of the Anomia Tribe, the term and character of Terebratula not being recognised by that author as generically distinct from the Anomia. Our reasons for this deviation shall be explained as briefly as it is possible: from the nature of those remarks, and the extent of enquiry with which it is connected, this cannot however be comprised within very slender limits.