BOOK REVIEWS 



377 



written by Mr. M. G. Kains, Lecturer on Horticulture, Columbia University. 

 Much of the matter would be of little value for the British reader, as, for instance, 

 the pruning of Peaches, Nectarines, Grapes, &c, in the open; but even on these 

 subjects there is a good deal of instructive matter that the grower of these fruits 

 under glass in this country could read with benefit to himself. Many will not 

 agree with a translation from Karl Koopmann : " The less a tree is cut 

 the sounder it will be, and the better its fruits." Though the knife is indis- 

 pensable in many cases, there is no question it is frequently used recklessly and 

 does more harm than good, and is a source of disease and bad health to trees. 

 On all sides we see instances of poor pruning by not making clean cuts, by 

 the dead snags of branches, and holes right into the main branches or into the 

 trunk itself, of trees that have had limbs cut improperly, and in a way impossible 

 to heal over, an effort Nature always makes. The chapters on Pruning Principles, 

 How Wounds Heal, and Prevention of Injuries, are worthy of the closest 

 attention of all tree-lovers, and should receive far more study in the future than 

 has been given in the past, in the case of both old and young trees. The 

 illustrations are not only numerous, but capital guides on what to do and what 

 not to do, if health and fertility are to be maintained, and planting, training, 

 diseases, and tools most suitable to use are fully dealt with. In brief, it is a work 

 that we can strongly recommend to all interested in this important matter. The 

 book is excellently printed and well indexed. 



" Heredity." By J. Arthur Thomson, M.A., LL.D. Ed. 3. 8vo. 627 pp. 

 (Murray, London, 1919.) 15s. net. 



The call for a new edition of this excellent work has enabled the author to 

 correct a few errors, and to make a few slight alterations in the text. 



" Profitable Herb Growing and Collecting." By A. B. Teetgen. Ed; 2. 

 8vo. xi + 195 pp. (Country Life, London, 1919.) 5s. net. 



The war has turned the attention of many to the growing of medicinal plants, 

 who before knew not that our main supplies were derived from the Continent. 

 Since the war is happily at an end whether or not their cultivation will prove 

 profitable here will depend upon the price for which the Continental senders can 

 supply them. To everyone who essays to grow them we may, however, recom- 

 mend this book with all confidence as a trustworthy guide, so long as he bears 

 in mind that it was written with war conditions in view. 



" Mendelism." By R. C. Punnett, F.R.S. Ed. 5. 8vo. xv + 219 pp. 

 (Macmillan, London, 1919.) 75. 6d. net. 



First published in 1905, revised from time to time, and translated into German, 

 Swedish, Russian, and Japanese, Professor Punnett's clear account of Mendelism, 

 and gradual developments towards a complete solution of the problem of heredity, 

 needs no other recommendation. This new edition contains two chapters 

 additional to those which made the fourth edition, describing the American 

 experiments on heredity in the fruit-fly, Drosophila. Not only the student, but 

 the general reader who wishes to keep abreast of the work done in one of the most 

 fascinating branches of natural history, will find a lucid exposition in this well- 

 printed and illustrated book. 



" The Flower and the Bee." By John H. Lovell. 8vo. 278 pp., 119 figs. 

 (Constable, London, 1919.) 105. 6d. net. 



This book deals very completely with the value of insects in pollination, 

 and is a modern popular edition of Hermann Mueller's " The Fertilization of 

 Flowers." There are over a hundred photographs of American plants, showing 

 the comparison between wind- and insect- pollinated flowers and their relation to 

 insects. 



Carl Vogt's, the German scientist, opinion is quoted, namely, " That the power 

 and wealth of the English nation is due to bumble-bees, as they pollinate red 

 clover, which is food for the famous English beef " ! 



Examples are given of bee, butterfly, hawk-moth, fly, and beetle-pollinated 

 flowers, and the comparative value of anemophilous and entomophilous flowers, 

 and the differences between pollen and nectar flowers are described. 



The last chapter is devoted to the extreme importance of bees in fruit- 

 growing. 



