Table 9 fig: 1 pag: 226. To the rt reverend father in god john ld. Bishop of ely, this plate, in memory of his lordships many & great favours is gratefully dedicated by j. M. M. A. & f. R. S. [john morton, master of arts and fellow of the royal society]. Text: "74. Of the conchae ammoniae, and ammonitae, we have several sorts. They are as follows. . "72. Proceed we now to the turbinated shells and stones of the second class, that is, those that are spirally turn'd, and of a flat depressed shape. These are of two kinds: in the first, the smaller convolutions do not appear externally, being swallow'd up, as it were, by the largest, that is, by the outmost wreath. These are called nautili or sailers. In the second, the whole number of wreaths appear plainly: and the shell is generally of a more depressed shape. To these i shall assign the name of conchae ammoniae, and to the stones form'd in them of ammonitae; which names are given by naturalists, as in some manner they resemble those wreathed horns which are usually seen upon the heads of the images of jupiter ammon. Most of these of both kinds, i now speak of the fossil ones, have their cavitity divided into sundry cells or apartments, by means of transverse shelly partitions, as in the sea nautilis: and have these partitions placed at certain short distances one from another, as in that. The fossil nautili, and so for the ammoniae with us, are always found filled with a stoney or other like matter. The shells of this second sort that are found enclosing and covering a stoney matter: as also the stones that originally formed in them, that are now found disclos'd and uncover'd, are generally called in england snake-stones and serpentine stones; because in the fashion of their wreath-wrok they somewhat resemble a folded snake. To many of the stones thus formed there adhere some remains of the shell that form'd them; especially in the intervals of the striae, and in the central part of them; these, as being less prominent, being less expos'd to injury. But with us, 'tis not very usual to meet with any of the ammoniae entire. Some of them have quite disappear'd; excepting only their shelly partitions, by authors usually called diaphragms, which lying enclos'd, and as it were, wedged in stone, have been generally well preserv'd from those external injuries that destroy'd the exteriour part: and so the stone is left bare. . "79. (5. ) the five-wreath'd double striated ammonia, beset with a row of short studs upon each side of its back. It is not unfrequently found with us in digging into clay at oxendon, and thereabouts, and appears by its prominencies to be a different sort of ammonia from that above-mentioned; there being no footsteps of any such spikes in that. Besides, it is too thick, the outmost wreath especially: and too much depressed in the central part, to be an ammonia of the fourth species; however it agrees with it in other particulars. ". Date: 1712.
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