Nabikoáguna Mnemonic. Fig. 1, plate IV. This is the head of an infant represented in the fine red pipe-stone from the Missouri. Locality, site of the ancient fort of the Kasonda valley. [I. Keeler, junior.] [Illustration: AMERICAN ANTIQUITIES—Plate IV.] CLASS SECOND.—MEDÄEKA. This class comprises the amulets proper. All the objects of this class are supposed to have been worn on various parts of the person, as a defence against witchcraft, sorcery, or spells, or to propitiate good luck by superstitious means. Medäeka Missouri. See Fig. 1, Plate V, with the illustration of the manner of its being worn on the breast. This article varies moderately in length, breadth and figure. It is generally the frustum of an acute pyramid, perforated in its length, to admit being suspended from the neck, or ears. The figure exhibited is three inches in length by two-tenths in breadth at its superior, and nine-tenths at its inferior extremity. Sometimes, as in the figure given, it has a raised surface in the direction of the perforation. It is formed of the red pipe-stone of the Coteau Des Prairie, west of the Mississippi; and its disinterment from Indian graves in western New-York, denotes an early traffic or exchange of the article, or rather the material of its construction, with the tribes in that quarter. This stone is fissile, and easily cut or ground by trituration with harder substances to any figure. It bears a dull gloss, not a polish, which was produced by rubbing the surface with the equisetum, or rush, which has a silicious gritty surface. It is of the period anterior to the introduction of European arts. The specimen figured is from Onondaga county, [I. V. V. Clarke.] It occurred also at Oswego, in removing the elevation of the old fort. [J. McNiel.] Also, at Lower Sandusky, Ohio. [L. Cass.] [Illustration: AMERICAN ANTIQUITIES.—Plate V.] Medäeka Dental. Fig. 4, 5. Plate VI. Fossil specimens of the bear’s tooth. A power against charms or spells was often attributed to amulets of this kind. The two species, very different in size, and of course the age of the animal, were obtained from a single grave. Valley of the Genesee river. [E. Trowbridge.] Medäeka Okun. Fig. 3, Plate VI. This species is made from a compact kind of bone, squared and perforated. Valley of the Genesee river. [E. Trowbridge.] From an ancient grave. [Illustration: AMERICAN ANTIQUITIES.—Plate VI.] CLASS THIRD.—ATTAJEGUNA.[71] [71] From the Algonquin JEEGUN, an instrument, an implement, or any artificial contrivance, or invention.