40 



NATURE 



[March io, 192 i 



certain conditions are known). With a good 

 modern lens aberrations are negligible, and every 

 other factor may be determined more or less accu- 

 rately ; the greater the accuracy attained in the 

 estimation of the factors — height and such like — 

 the greater will be the accuracy of the resulting 

 compilation. 



The conceptions of metrophotography and 

 photogrammetry do not seem to find any mention 

 in the book. It is almost inconceivable that 

 an author should devote a section of his 

 book to aerial mapping without any reference 

 to the work already done in survey by photo- 

 graphy from balloons. The subject of mapping 

 by aerial photography was of vital importance in 

 the war, and is the most promising outlet for the 

 aeroplane camera in peace; its inadequate treat- 

 ment here forms a serious blemish on an other- 

 wise useful book. H. H. T.^ 



Our Bookshelf. 



The Flowering Plants of South Africa. Edited by 

 Dr. I. B. Pole Evans. Vol. i. No. i, Novem- 

 ber, 1920. Pp. ii-f-10 plates. (London: L. 

 Reeve and Co. , Ltd. ; South Africa : The Speci- 

 ality Press of South Africa, 1920.) 15^-^ 

 coloured; 10s., plain. 

 European gardens owe so much to South Africa 

 for the plants which adorn them that the appear- 

 ance of a South African Botanical Magazine is 

 an event of considerable interest. Dr. L B. Pole 

 Evans, the energetic Director of the Botanical 

 Survey of South Africa, who is editing "The 

 Flowering Plants of South Africa," is to be con- 

 gratulated on this new venture to bring the 

 treasures of the South African flora to the notice 

 of a wider public. In the preface it is stated that 

 the publication is due to the keenness and interest 

 of a South African lady, "whose love for her 

 country and its natural beauties has been the 

 means of procuring the necessary funds for the 

 initiation of the work. " The plants illustrated will 

 represent so far as possible the flowering plants 

 of the several provinces of the Union of South 

 Africa. 



It is unfortunate that in this first number the 

 plants depicted, though familiar garden plants, are 

 not for the most part of very special interest, and 

 it is to be hoped that in succeeding numbers some 

 of the less known and more striking flowers of 

 South Africa will be represented. 



The work being prepared in South Africa and 

 produced in England has suffered considerably, 

 and both the illustrations and the descriptions leave 

 a good deal to be desired. The printing of the 

 names at the foot of the plates is also unfortunate 

 in view of the corrections that have had to be 

 made in England in the text of plates 3 and 4, so 

 that an incorrect name appears on each plate. 



The experience gained from the publication of 

 this first number will, we hope, lead to a con- 

 NO. 2680, VOL. 107] 



siderable improvement in following numbers. In 

 making criticisms on this useful and interest- 

 ing venture it is realised fully how great the 

 difficulties in its production must have been. 



The Garden Doctor : Plants in Health and Disease, 

 By F. J. Chittenden. Pp. x-t-154. (London: 

 Country Life, Ltd. ; New York : Charles 

 Scribner's Sons, 1920.) 7s. 6d. net. 

 There are few gardeners, even scientific ones^ 

 who will not learn much from these pages, for 

 Mr. Chittenden's position at Wisley gives him 

 many opportunities of ascertaining the common 

 pests of plants and their appropriate treatment. 

 After giving an excellent and popular synopsis of 

 the structure and physiology of the plant, he treats 

 of those ailments due not so much to parasites 

 as to wrong treatment. He deals with fungus 

 pests by mentioning the common plants in alpha- 

 betical order, and in a few words sketches both 

 diseases and treatment. His chapter on insect 

 pests is not so good, though here, as throughout 

 the book, he deals with principles, and if these 

 are grasped the reader should be able to diagnose 

 the nature, at any rate, of most of the common 

 pests. There are chapters on fungicides, insecti- 

 cides, and spraying generally, the usual formulae 

 being given. The illustrations on the whole are 

 excellent, but lose much of their usefulness by 

 having no text references, and appear to have 

 been collected casually. Several of them are taken 

 from the Ministry of Agriculture leaflets without 

 acknowledgment, while others are of pests not 

 mentioned in the book. The reference to the 

 winged form of American blight as the "fly," and 

 to the apterous form as the "insect," is not to be 

 commended, while the full explanation of the plate 

 of the "Daffodil Fly," which has a humorous 

 touch, would be interesting. Despite minor 

 criticisms which might be made, this is a most 

 readable and interesting book. G. C. G. 



The Birds of the British Isles and their Eggs. By 

 T. A. Coward. Second series. Families Anat- 

 idae to Tetraonidae. Pp. vii -l- 376 -M 59 plates. 

 (London and New York : Frederick Warne and 

 Co., Ltd., 1920.) 12s. 6d. net. 

 This second series completes Mr. Coward's work 

 on British birds, already favourably noticed in the 

 pages of Nature, It treats of the numerous and 

 varied forms of aquatic and wading birds, storks, 

 bustards, rails, pigeons, and the game-birds. The 

 coloured figures, which represent practically every 

 species, have been nicely reproduced in miniature 

 from the late Lord Lilford's well-known book, 

 most of them being the work of Mr. Archibald 

 Thorburn. The coloured figures of the eggs are 

 less satisfactory, but may be regarded as accept- 

 able. In addition to these plates there are sixty- 

 nine photographic illustrations of both birds and 

 their nesting haunts. This wealth of illustration, in 

 conjunction with the author's excellent and ap- 

 propriate letterpress, renders this work the best of 

 the minor books devoted to a subject which is 

 ever growing in popularity. 



