LEHRBUCH DER MINERALOGIE, by W. Schmidt and E. Baier. Second Edition, revised and enlarged by E. Baier, 376 pp., 302 illustrations and one colored plate, 16X24 cm. Birkhaüser Verlag, Basel, Switzerland, and Stuttgart, Germany, 1955. Price, bound, 35 DM.
CLAYS AND CLAY MINERALS, Edited by Ada Swineeord and Norman Plummer. National Academy of Sciences, National Research Council Pubi.327, viii+498+index, Washington, D. C., 1954 (1955), $4.00. (Proc. 2nd Natl. Conference on Clays and Clay Minerals, Columbia, Mo., Oct. 15-17, 1953).