—, foliaceous, of Vesuvius, xi, 267.
— and potash, sulphate of, xx, 195.
—, native, in Connecticut, i, 55; vi, 230; xxxiii, 160.
—, —, connection with trap in Connecticut and Michigan, xlvii, 132.
—, —, in drift, Massachusetts, E. Hitchcock, xlv, 331.
—, —, in N. Jersey, Summerville mine, v, 401; xxxvi, 107.
—, —, —, L. C. Beck, xlv, 331.
—, —, of Michigan, D. Houghton, xli, 185; xlv, 331, 332.
—, —, mass of, from Lake Superior, H. R. Schoolcraft, iii, 201.f
—, —, —, presented to Yale College, xxvii, 381.