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 thus formed; it will be no dificult task to account for the different sections and broken parts of the Belemnite; and in what manner they were reduced to the several forms or appearances, in which we commonly find them.

The better to illustrate my conjecture, I shall first exhibit some drawings, which shew the several specimens broken and imperfect; and then propose my sentiments concerning them before they were deserted by their inhabitants. Figure 6. shews the spine of the echinus ovarius broken obliquely, as is common to all of them. Figure 5. exhibits the inward structure of the Belemnite, when broken horizontally, with the central rays. Figure xi. is the same Belemnite split through its axis. Figure xii, and xiii, are broken in the same direction as Fig. 5. and xi, and shew how the several laminæ are placed one over another in the manner, in which it is formed. Fig. xiv. shews the Belemnite in the most perfect state we ever find it. Fig. 4. is the fusiform Belemnite found in chalk, which has been often taken for a spine. a, which is the termination of the conical cavity, has been thought to be the socket of the spine, which receives the papilla, when growing to the echinus; but, when compared with the socket of the true spine, we find it widely different. The pricked lines b, c. b, c. shew what the fusiform Belemnite was, when perfect, with the alveolus d, c. Many of

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