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JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



unless such can affect the reproductive structures and not the soma only. 

 He says the Darwin- Wallace theory involves : (1) variation, (2) inherit- 

 ance of it, (3) elimination of the less fit &c. by natural selection. No 

 one disputes the first two ; but Darwin never gave a case of his so-called 

 " influencing " variations required for natural selection. On the other 

 hand, later in life he recognized the possible needlessness of natural 

 selection. The author next describes Mendelism, but makes a dis- 

 tinction between the soma and the gametes, and considers the terms 

 "dominant" and "recessive" as misleading; but the reader must 

 be referred to the book for his reasons. 



Stress is laid on Biometry in considering variations ; but the author 

 overlooks the fact that no merely numerical prohahilities can account 

 for adaptations with purpose in variations. He advances his own 

 theory, called An Intrinsic Theory of Variation and Transmission, by 

 which he would apply biometry to the microscopical gametes, observing 

 " the determinants of the unit-characters in [the primitive germ-cells] 

 are arranged according to the Law of Probability." He next discusses 

 De Yries' Mutation theory, and devotes tv/o chapters or essays to 

 Heredity.. We then have two more, on Bees; on Evolution and Con- 

 troversy; the 'Handicap of Sex; Evolution in Eeligion; and lastly, 

 men who have revealed themselves. 



" Wild Flowers of the British Isles." By H. Isabel Adams, 

 F.L.S. Eevised by James Bagnall, F.L.S. Vol. II. Large 8vo., 

 199 pp., 62 coloured plates. (Heinemann, London, 1910.) 30s. net. 



On the title-page we read " completing the British w^ild flowers, 

 with the exception of water-plants and trees. " Why these are omitted 

 (as we note i?oiioma and Acorns are described) is not clear. 



The flowers and dissections are very clear; but, as in Vol. I., it is 

 unfortunate that the plants figured are so crowded; but this, we sup- 

 pose, was inevitable ; . and when . not crowded the space is filled with 

 text. 



" Fifty Years of Darwinism: Modern Aspects of Evolution; being 

 Centennial Addresses in Honour of Charles Darwin, before the Ameri- 

 can Association for the Advancement of Science, Baltimore, January 1, 

 1909." 8vo., 274 pp. (Holt, New York; Bell, London, 1909.) 8s. 



With the exception of the first, by Professor Poulton on "Fifty 

 Years of Darwinism," all the addresses are by Americans. They 

 deal with (in brief) " The Theory of Natural Selection from the Stand- 

 point of Botany," "Isolation," "The Cell," "Direct Influence of 

 Environment," " Unit Characters in Heredity," " Mutation/' " Adap- 

 tation," " Darwin and Palaeontology," " Evolution and Psychology." 



Mr. Coulter, who writes the second, begins with the important 

 recognition that Darwin's " historical- position in plant physiology 

 and in plant ecology is one of the first rank." He emphasizes the 

 fact that " selection does not originate- charactei's,' and alludes to 



