Xanthic oxide in guano, xlix, 200.

Xanthine, Unger, xlix, 391.

Xanthite, a new mineral, W. W. Mather, xviii, 359f, [Idocrase.]

—, formula from the analysis, J. J. Berzelius, xxvi, 388.

Xanthium maculatum, memoir on, C. S. Rafinesque, i, 151.

Xanthogen, discovery of, vii, 377.

Xavier, F., death of, xxiv, 194.

Xyloidine, H. Braconnot, xxviii, 131.

Y.

Yale College Observatory, latitude and longitude of, xxxiv, 309.