OSTRACITES, in natural history, the name by which authors call the fossil oyster-shell.

Ostracites has the same medicinal virtues with the blemmites, and lapis judaicus, only in a higher degree; being accounted by Dr. Lister one of the greatest known medicines in nephritic cases: the dose, in powder, is from half a dram to a dram, in white-wine; and to prevent a sickness at the stomach, that sometimes attends the taking it, one third part of the quantity of powdered chamomile-flowers may be mixed with it.