XII. THE HISTORY OF THE CONFLICT BETWEEN RELIGION AND SCIENCE. By J. W. Draper, M. D., LL. D. $1.75.

XIII. THE DOCTRINE OF DESCENT AND DARWINISM. By Professor Oscar Schmidt (Strasburg University). With 26 Illustrations. $1.50.

XIV. THE CHEMICAL EFFECTS OF LIGHT AND PHOTOGRAPHY. By Dr. Hermann Vogel (Polytechnic Academy of Berlin). Translation thoroughly revised. With 100 Illustrations. $2.00.

XV. FUNGI: Their Nature, Influences, Uses, etc. By M. C. Cooke, M. A., LL. D. Edited by the Rev. M. J. Berkeley, M. A., F. L. S. With 109 Illustrations. $1.50.

XVI. THE LIFE AND GROWTH OF LANGUAGE. By Professor William Dwight Whitney, of Yale College. $1.50.

XVII. MONEY AND THE MECHANISM OF EXCHANGE. By W. Stanley Jevons, M. A., F. R. S. $1.75.

XVIII. THE NATURE OF LIGHT, with a General Account of Physical Optics. By Dr. Eugene Lommel. With 188 Illustrations and a Table of Spectra in Chromo-lithography. $2.00.

XIX. ANIMAL PARASITES AND MESSMATES. By Monsieur Van Beneden. With 83 Illustrations. $1.50.

XX. FERMENTATION. By Professor Schützenberger. With 28 Illustrations. $1.50.

XXI. THE FIVE SENSES OF MAN. By Professor Bernstein. With 91 Illustrations. $1.75.