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 subject, so (if I may be allowed the comparison) I received farther information by luckily meeting with a Belemnite, whose laminæ were in a manner dissected and laid open by the vague acid, or some other corroding menstruum, which every where pervades the earth, destroying some bodies, and forming others. The laminæ of this truly wonderful body are here exposed to view, and plainly shew us, that nature, in this, as in all her works, pursues the most simple, easy, and shortest methods, though they appear ever fo intricate and interwoven. This specimen will, I hope, serve to explain a matter, which hath so long puzzled the curious in natural history; and convince us, that there is nothing more wonderful in the formation of the Belemnite, than in that of a cockle, oyster, or any other testaceous substance; with this difference only, the oyster strengthens its shell, and excludes its first habitation, by additional laminæ formed within; the Belemnite incloses its dwelling by adding new laminæ without. Figure X. represents the Belemnite split up the middle, with the siphunculus in the front: a, b exhibit the first formed cell, or seat of the animal ab ovo. As the animal grows larger, it forms a second cell or chamber b to c, at the same time covers the first cell, by forming theappendage [sic] or guard c, i, which is the first stage of the Belemnite. In forming the third cell c, d, fresh laminæ or coverings are carried on from d, to k; and so of the rest, e, f, g, h; or l, m, n, o. When we have duly considered the manner, in which the shell is

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