Ammonite
a fossil shell belonging to an extensive genus of extinct mollusks. They were allied to the chambered nautilus. The shells were lined with pearl and furnished with partitions. The fossils vary in size from a pin head to shells four feet in diameter. All are curled up like flat snail shells. Ammonites have a fancied resemblance to a ram's horn, or the horn of Jupiter Ammon, whence the name. In Scott's Marmion, Whitby's nuns tell their hosts of Lindisfarne:
How, of thousand snakes, each one
Was changed into a coil of stone
When holy Hilda prayed;
Themselves, within their holy bound
Their stony folds had often found.
Was changed into a coil of stone
When holy Hilda prayed;
Themselves, within their holy bound
Their stony folds had often found.
Volume I · Aiton’s Encyclopedia