Of the Nautelites, by the Ancients called Cornua Ammonis (for its resemblance of the curled Horns of the Ram, worshipped by the Name of Jupiter Ammon in the Deserts of Africa:) Here are various Sorts, of different Colours, Figures and Sizes, from less than half an Inch to half a Foot in Diameter; but all so curled up that the Tail of the Snake is in the Center of the Stone. The small Sort, whose Parts are protuberant and swelling to a Round; of these are both the Ash-coloured, and the brown (from my Lord Bp of Carl.) the Striæ of each Colour are single near the Center, but presently divide into two Lines, but terminate in a single Lineation. Of the same Form are a greater Sort that are six Inches in Circumference, and very fair. These of the Ash-coloured Stone, appear in Places to be adorned with a shining brazen Armature, as is more evident by an Arch, or Part of another of the same Kind. A Segment of a large one with single Striæ of an Iron-stone; it is 4 ½ Inches round. One that is more thinly striated, but the Lineations are larger and more prominent, like N° 10 in Dr. Plot's 5 Tab. Nat. Hist. Oxon. On the other Side is no Figure, being of Dr. Lister's 9th Sort (g)(g) De Lapid. turbin. p. 212, ex altera tantum parte ad umbilicum cavus. Of those that are depressed; here is one of five Wreaths, three Inches broad; and another near half a Yard in Circumference, which was the largest I could conveniently bring from Whitby; both these which are an Ash or blewish Stone are of the Cornua Ammonis pertusa, being perforated at the Center; they have also a Crest or sharp Ridge, like the Spina Dorsalis; on each Side of which is a Furrow or Channel. A Fragment of a small one with as many Wreaths. The Segment of a larger, being half a Foot round; my kind Benefactor, Dr. Woodward, received it from Whitton Com. Linc. as he did three Samples of the lesser Sort from Lansdown, near Bath. My Lord Bishop of Carlisle sent me, amongst others, the smallest I have seen, being but a Quarter of an Inch broad, yet fairly striated. A larger with six Wreaths. Mr. Sutherland of Edinburgh sent me a small compress'd one, found about ten Miles from the City. But here is another Species, considerably different from all the former, the middle Part being sunk in, or depress'd to a great Depth; the outmost Wreath is above two Inches broad, the Center on each Side is dip'd in, an Inch deep; it is near eight Inches in Circumfe ferencerence. A small one of the same Sort, but one Inch broad, and of a shining Colour. Here are also the Matrix or Beds they are lodged in, somewhat globular, and without any Impression on the convex Part, but finely striated within, after the Form of the Stone it self. The most remarkable of which was given me by Dr. Sawry of Yorke, who received it from Whitby; it is a Congeries of them in an oval Brass Lump (as commonly called) a Quarter of a Yard round, containing the gilded impressions of seven of them.