The importance of this work is twofold. In the first place, it sums up the teaching of one of Darwin's greatest successors, who has been for many years a leader in biological progress. As Professor Weismann has from time to time during the last quarter of a century frankly altered some of his positions, this deliberate summing up of his mature conclusions is very valuable. In the second place, as the volumes discuss all the chief problems of organic evolution, they form a reliable guide to the whole subject, and may be regarded as furnishing--what is much needed--a Text-book of Evolution Theory. =ANIMAL BEHAVIOUR.= By C. LLOYD MORGAN, LL.D., F.R.S., Principal of University College Bristol, author of 'Animal Life and Intelligence,' etc. With numerous Illustrations. Large crown 8vo., 10s. 6d. =HABIT AND INSTINCT.= By C. LLOYD MORGAN, LL.D., F.R.S. With Photogravure Frontispiece. viii + 352 pages. Demy 8vo., cloth, 16s. =A TEXT-BOOK OF ZOOLOGY.= By G. P. MUDGE, A.R.C.Sc. Lond., Lecturer on Biology at the London School of Medicine for Women, and the Polytechnic Institute, Regent Street. With about 200 original Illustrations. Crown 8vo., cloth, 7s. 6d. =ELEMENTARY NATURAL PHILOSOPHY.= By ALFRED EARL, M.A., Assistant Master at Tonbridge School. With numerous Illustrations and Diagrams. Crown 8vo., cloth, 4s. 6d. =A CLASS-BOOK OF BOTANY.= By G. P. MUDGE, A.R.C.Sc. Lond., F.Z.S., and A. J. MASLEN, F.L.S., Lecturer on Botany at the Woolwich Polytechnic. With over 200 Illustrations. Crown 8vo., 7s. 6d. =THE BECQUEREL RAYS AND THE PROPERTIES OF RADIUM.= By the Hon. R. J. STRUTT, Fellow of Trinity College, Cambridge. With Diagrams. Demy 8vo. 8s. 6d. net. =A MANUAL OF ALCOHOLIC FERMENTATION AND THE ALLIED INDUSTRIES.= By CHARLES G. MATTHEWS, F.I.C., F.C.S., etc. Fully Illustrated. Crown 8vo., cloth, 7s. 6d. net. =WOOD.= A Manual of the Natural History and Industrial Applications of the Timbers of Commerce. By G. S. BOULGER, F.L.S., F.G.S. Fully Illustrated. Crown 8vo., 7s. 6d. net. =PSYCHOLOGY FOR TEACHERS.= By C. LLOYD MORGAN, LL.D., F.R.S. xii + 251 pages. Crown 8vo., 3s. 6d. =ANIMAL SKETCHES.= By C. LLOYD MORGAN, LL.D., F.R.S. viii + 312 pages, with 52 Illustrations (many of them full-page). Crown 8vo., cloth, 3s. 6d. _LONDON: EDWARD ARNOLD, 41 & 43 MADDOX STREET, W._ Footnotes: [1] The inferior planet Venus comes closer, but is not visible throughout the night. [2] The facts were collected with great care and ability by S. P. Rigaud, and published by the Oxford University Press in 1832 as "Miscellaneous Works and Correspondence of the Rev. James Bradley." [3] Since the light must travel from the sun to Saturn _and back again to the earth_, the interval would be more nearly 150 minutes. [4] Monthly Notices of the Royal Astronomical Society, vol. xvii. p. 126. [5] This should be Cambridge, _Mass._