=V. The Study of Sociology.= By Herbert Spencer. Seventh Edition. Crown 8vo. Cloth, price 5_s._ =VI. On the Conservation of Energy.= By Balfour Stewart, M.A., LL.D., F.R.S. With 14 Illustrations. Fifth Edition. Crown 8vo. Cloth, price 5_s._ =VII. Animal Locomotion=; or, Walking, Swimming, and Flying. By J. B. Pettigrew, M.D., F.R.S., &c. With 130 Illustrations. Second Edition. Crown 8vo. Cloth, price 5_s._ =VIII. Responsibility in Mental Disease.= By Henry Maudsley, M.D. Third Edition. Crown 8vo. Cloth, price 5_s._ =IX. The New Chemistry.= By Professor J. P. Cooke, of the Harvard University. With 31 Illustrations. Fourth Edition. Crown 8vo. Cloth, price 5_s._ =X. The Science of Law.= By Professor Sheldon Amos. Third Edition. Crown 8vo. Cloth, price 5_s._ =XI. Animal Mechanism.= A Treatise on Terrestrial and Aerial Locomotion. By Professor E. J. Marey. With 117 Illustrations. Second Edition. Crown 8vo. Cloth, price 5_s._ =XII. The Doctrine of Descent and Darwinism.= By Professor Oscar Schmidt (Strasburg University). With 26 Illustrations. Third Edition. Crown 8vo. Cloth, price 5_s._ =XIII. The History of the Conflict between Religion and Science.= By J. W. Draper, M.D., LL.D. Eleventh Edition. Crown 8vo. Cloth, price 5_s._ =XIV. Fungi=; their Nature, Influences, Uses, &c. By M. C. Cooke, M.A., LL.D. Edited by the Rev. M. J. Berkeley, M.A., F.L.S. With numerous Illustrations. Second Edition. Crown 8vo. Cloth, price 5_s._ =XV. The Chemical Effects of Light and Photography.= By Dr. Hermann Vogel (Polytechnic Academy of Berlin). With 100 Illustrations. Third and Revised Edition. Crown 8vo. Cloth, price 5_s._ =XVI. The Life and Growth of Language.= By William Dwight Whitney, Professor of Sanskrit and Comparative Philology in Yale College, New Haven. Second Edition. Crown 8vo. Cloth, price 5_s._ =XVII. Money and the Mechanism of Exchange.= By W. Stanley Jevons, M.A., F.R.S. Fourth Edition. Crown 8vo. Cloth, price 5_s._ =XVIII. The Nature of Light=: With a General Account of Physical Optics. By Dr. Eugene Lommel, Professor of Physics in the University of Erlangen. With 188 Illustrations and a table of Spectra in Chromo-lithography. Second Edition. Crown 8vo. Cloth, price 5_s._ =XIX. Animal Parasites and Messmates.= By Monsieur Van Beneden, Professor of the University of Louvain, Correspondent of the Institute of France. With 83 Illustrations. Second Edition. Crown 8vo. Cloth, price 5_s._ =XX. Fermentation.= By Professor Schützenberger, Director of the Chemical Laboratory at the Sorbonne. With 28 Illustrations. Second Edition. Crown 8vo. Cloth, price 5_s._