DENDRITIC BLACK MANGANESE-ORE. Gcognosiic and Geographic Situations. It is a rare mineral, and generally occurs along with grey manganese-ore ; at Ehrenstock near Ilmenau, in crusting radiated grey antimony-ore. Third Subspecies. Dendritic Black Manganese-Ore. Dendritischer Schwarzbraunstein, Ilausmann. Manganese oxid6 noire brunfitre ramuleux, llavy, Tab. p. li t. (in part).—Dendritischer Schwartz Braunstein, liaus. Handb. ■ > s. 29‘*3. External Characters. Its colour is bluish-black, which passes into coal-black or iron-black. It occurs in dendritical external forms, which are dis posed either in the surface of rents, or distributed through the mass of minerals of dilferent kinds. It is dull. Geognostic and Geographic Situations. It occurs upon the surface or in the interior of* marty different minerals, as quartz, and marl-slate. It is found in the Ibcr" near Grund; and at Maria-Sprung near Gottingen. 3. Wad. This species is divided into three subspecies, viz. Ti- brous Wad, Ochry Wad, and Dendritic Wad. % 4. First