NATURE 



301 



THURSDAY, JUNE 19, 1919. 



TEXT-BOOKS OF BOTANY. 

 (i) Elements de Botanique. Par Prof. Ph. Van 



Tieghem. Tome i., "Botanique Gen^rale. " 



Cinquifeme edition, revue et corrigee par Prof. 



J. Costantin. . Pp. xv + 619. Tome ii., 



"Botanique Speciale. " Cinqui^me Edition, re- 



maniee et augmentde par Prof. J. Costantin. 



Pp. xx + 743. (Paris: Masson et Cie, 1918.) 



Price 14 francs. 

 (2) Botany: A Text-book for Senior Students. 



By D. Thoday. Second edition. Pp. xx + 524. 



(Cambridge: At the University Press, 1919.) 



Price 75. 6d. net. 

 '-.) Lowson's Text-book of Botany (Indian 



h.dition). Revised and adapted by Birbal Sahni 



and M. Willis. With a preface by Dr. J. C. 



Willis. New and revised edition. Pp. xii + 6io. 



(London : W. B. Clive, University Tutorial 



Press, Ltd., 1919.) Price 85. 6d. 

 {i) T^HE latest edition of Prof. Ph. Van 

 -•- Tieghem 's text-book, edited by Prof. J. 

 Costantin, is arranged on the same plan as pre- 

 vious editions. A serious omission from the point 

 of view of the bibliographer is the absence of any 

 prefatory note or introduction. The first volume 

 is described on the title-page as "revue et cor- 

 rigee, " and the second as " remani^e et aug- 

 mentee," but there is no indication as to the extent 

 or nature of the changes or additions by virtue 

 of which the present edition may be regarded as 

 an advance on earlier ones. A careful comparison 

 of the table of contents and the text is therefore 

 rendered necessary. There is very little change 

 in the first volume — that dealing with general 

 botany. The first five chapters deal respectively 

 -with the body of the plant as a whole, the root, 

 stem, leaf, and flower — in each case treated under 

 two sections : (i) form and structure, and 

 •(2) function. This treatment will probably not 

 •commend itself to teachers in this country at the 

 present time, if only from the difficulty it involves 

 in presenting an account of the physiology of the 

 plant as a living whole. In the next four chapters 

 an account is given of the life-history of the four 

 great subdivisions of the plant kingdom — Seed- 

 plants, Vascular Cryptogams, Mosses, and Thallo- 

 phytes. The difference between the origin or pro- 

 ducts of germination of the spore in the fern and 

 in the moss, as contrasted with each other and 

 with the seed-plant, is emphasised by the use of 

 special terms — the spore and sporangium of the 

 fern are termed "diode" and "diodange," those 

 ■ in the moss "tomies " and "tomiange," the whole 

 I sporogonium of the moss being a "tomiogone." 

 ) Vol. ii., "Special Botany," deals with classifica- 

 ; tion. Two subkingdoms are recognised — Arhizo- 

 ; phytes, or plants without roots, including the two 

 great divisions Thallophyta and Bryophyta ; and 

 Rhizophytes, or plants with roots, including the 

 great divisions Vascular Cryptogams and Phanero- 

 gams. The subdivision and systematic treatment 

 of the first three divisions are on familiar lines, but 

 NO. 2590, VOL. 103] 



those of the Phanerogams are widely different 

 from other systems which have been generally used, 

 such as that of Bentham and Hooker, which grew 

 out of the French system of Jussieu and De 

 Candolle, or that of Engler, which was a develop- 

 ment of Eichler's system. The system employed 

 in the present volume is based on that elaborated 

 by Van Tieghem in his paper entitled "The Eggs 

 of Plants considered as a Basis of Classification " 

 [Annales d. Sci. Natur., ser. 8, xiv.). The 

 Astigmat^es (Gymnosperms) fall into two classes 

 — Natrices with motile male cells, and Vectrices 

 with male cells non-motile. The Stigmat^es 

 (Angiosperms) include three classes — Monocotyle- 

 dons, Liorhizal Dicotyledons, and Dicotyledons. 

 The second is an extremely artificial group, con- 

 taining the grasses and water-lilies (except Nelum- 

 bium). For the subdivision of the other two great 

 groups of Angiosperms the details of the struc- 

 ture and development of the ovule are regarded as 

 supplying the most important characters. Special 

 stress is laid on the persistence or absorption of 

 the wall at the upper part of the embryo-sac; if 

 this remains intact up to the time of fertilisation, 

 the ovule is described as "perpariete "; if, on the 

 other hand, the wall has been absorbed before the 

 arrival of the pollen-tube, the ovule is " trans- 

 pariete. " Space does not allow of a detailed 

 criticism of the system, which provides many 

 puzzles for the British botanist who approaches it 

 with preconceived ideas of affinities based on a 

 knowledge of either of the systems to which refer- 

 ence has already been made. 



(2) The second edition of Mr. Thoday 's ad- 

 mirable elementary text-book differs from the 

 original edition of 191 5 in the addition of a small 

 supplementary section on Cryptogarris arranged 

 to cover the syllabus for the Cambridge Higher 

 School Certificate and similar examinations. The 

 fifty additional pages contain descriptions of the 

 structure and life-history of selected algae, fungi, 

 mosses and liverworts, and ferns. The examples 

 chosen are all common genera, and illustrate, so 

 far as possible in the small space allotted, the 

 variety in methods of reproduction among the 

 algae and fungi, while the relation between the 

 sexual and spore-bearing generations of the two 

 higher groups is treated in sufficient detail to 

 emphasise the principle of alternation of genera- 

 tions, and to render possible a comparison between 

 the life-history of the higher Cryptogams and the 

 Seed-plants. 



As in the former edition, the body of the text 

 is divided into five sections. In the first section 

 the functions of plant-organs and the work of 

 nutrition are treated experimentally ; the second 

 deals with the form and structure of the vegeta- 

 tive organs of seed-bearing plants, and the third 

 with the flower, seed, and seedling. Section iv., 

 on "The Classification of Plants," comprises, first, 

 a study of the floral types in the family Ranuncu- 

 lacea?, to illustrate the concept of species, genus, 

 and family, and the principles of floral evolution ; 

 and, secondly, a description of other floral types 

 as illustrated by a judicious selection of fifteen 



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