142 FLINT GENUS. mately grown together, that it is difficult to difcov* the faces of the concretions. Commonly tranflucent, but in fome varieties proaching to tranfparent. Hard. Not particularly difficultly frangible. It agrees in the remaining characters with the p je ‘ ■ ceding kind. Geognoflic Situation. It is found in agate veins, and is generally accoi®* panied with common amethyft. When both ki^ s occur together in the fame vein j the fibrous is ^ ways the oldeft, or adheres to the wall of the refit’ Geographic Situation. Nearly the fame as the former. SECOND