Jan. 8, 1885] 



NA TURE 



215 



the discussion as to the ascent of water in wood. No 

 doubt it is too early to anticipate where these researches 

 may lead ; meanwhile every botanical student should 

 learn the course of the vascular bundles in several typical 

 plants, say, among others, LatAyrus, Clematis, a Palm, 

 Tradescantia, a Fern such as Aspidiitm, and Equisetum. 

 This should be done not only with reference to the distri- 

 bution of these important structures, but also in order 

 that the study of transverse sections may become some- 

 thing more than the impression of a pattern on the 

 memory, as it too often is. 



The bearing of these matters on the older views which 

 confined the attention too much to the typical palm-type 

 for the Monocotyledons, and to a few restricted examples 

 of Dicotyledonous stems is obvious. 



Some very important points exist also with reference to 

 the structure of the vascular bundles, a matter which 

 should be studied as De Bary studied it, in connection 

 with the above. Students are seldom led to understand 

 that the terminations and interconnections of vascular 

 bundles often differ considerably from the enlarged por- 

 tions of the bundles, or " bundle-trunks," as the translators 

 term them. The classification of vascular bundles into 

 collateral, concentric, and radial has become better known 

 of late years ; but even now too little attention is paid to 

 the subject of the structure and development of the 

 vascular-bundle system in roots. This should be all 

 altered now, for it is difficult to imagine better guidance 

 for teachers and students than is afforded by the work 

 under review, and specialists will not be able to dispense 

 with it. 



Want of space prevents our entering further into some 

 other weighty matters in this portion of the work. No 

 doubt some difficulty will be felt by the uninitiated with 

 regard to De Bary's treatment of the subject of scleren- 

 chyma. The key to the difficulties consists in the fact that 

 however convenient it may be to regard the sclerenchy- 

 matous fibres of the "hard-bast" as part of the " fibro- 

 vascular " bundle, sclerenchyma may be regarded as a 

 form of strengthening tissue which recurs in various 

 positions, and may therefore be treated separately -that 

 which occurs as strengthening tissue associated with the 

 vascular bundles being called bast-fibres, and treated as 

 part of the bundle (which then becomes " fibro-vascular") 

 for no other reason than because it is convenient, and the 

 name is an established one. Simple as the matter is 

 when understood on anatomical grounds, we fear that 

 confusion will still ensue from want of care in apprehend- 

 ing the state of the case ; this will be due to no fault on 

 the part of the translators, however, for the portions of 

 the book dealing with these particulars leave little to be 

 desired. 



The second section of Part 1 1., treating of the secondary- 

 changes produced in the arrangement of the tissues by- 

 growth in thickness, forms a part of the book which has 

 had much influence on text-books since it was written. 

 The account of the growth in thickness by means of a 

 cambium zone is excellent, and should be carefully studied 

 by every botanist. The concluding portions of the book 

 are in some respects more adapted for the specialist than 

 for the ordinary student, but we do not advise the latter 

 to neglect them on that account ; on the contrary, much 

 of the foregoing information becomes clearer when con- 



trasted with the more abnormal processes observed in 

 the forms there treated of. The facts are somewhat more 

 isolated, however, and can only become important in 

 proportion as the earlier parts of the book are under- 

 stood ; moreover, work remains to be done among the 

 more anomalous forms. 



Enough has been written to show that no botanist will 

 be able to dispense with the work, and it only remains to 

 point out one or two faults in the translation, and 

 perhaps to mention a few trivial matters which might 

 have been put better. Such phrases as "a numerous 

 group of large . . . cells (p. 21), "the morphologically 

 lower leaf-surface" (p. 319), and "quite a few rows" (p. 

 372), are somewhat harsh, and result from the close ren- 

 dering of the original ; objection may also be taken to 

 such employment of compounds as " air-and-water- 

 containing" (p. 210) and "many-layered, chlorophyll- 

 containing parenchyma " (p. 226). It is true that students 

 of science who read much German find less difficulty from 

 the recurrence of such forms in English than might 

 be expected, but many will regard them as serious 

 blemishes which render the book more difficult to read. 

 Commelyna (p. 40) becomes " Commelina" subsequently 

 (p. 270 e.g.) we believe the former is correct, the latter 

 being the German spelling. " Equiseta " and " Gramina " 

 {e.g. p. 213), and " Orobanches" (p. 384) are not elegant. 

 The reference to Fig. 207 on p. 467 is wrong, that figure 

 concerning Cylisus. No doubt the misprint stands for 

 200. 



The translators are responsible for several terms which 

 will be new to English botany, and we must admit our 

 indebtedness to them for attempting to introduce definite 

 English equivalents for such terms as " Biindel-stamme" 

 "Holz-strdnge," "A'eien zellen" and "Ersatz-faserzellen." 

 Whether "bundle-trunks," "ligneous bundles," "subsidiary 

 cells," and "intermediate cells" respectively will be 

 generally accepted as the equivalents in English remains 

 to be seen. Personally we regard them with favour, as 

 serviceable representatives of terms which have their 

 uses. However, we can do no more here than congratu- 

 late the translators on having placed one of the most im- 

 portant scientific works of the day in the hands of British 

 botanists in a satisfactory form ; and we no less heartily 

 congratulate those botanists who have been debarred 

 from reading it in the original German on the rich store 

 so \vell placed before them. 



OUR BOOK SHELF 

 The Solar System. By Ernest R. G. Groth, M.D. 



Pp. 34. (London : John Bale and Sons, 1884.) 

 THIS book contains a very imperfect account of the 

 nebular hypothesis of Laplace and Kant, with certain 

 variations which must be incorrect, because they violate 

 mechanical principles, and with certain speculations 

 which are valueless because they are based on mere 

 imagination. 



The author does not realise the relativity of force and 

 motion, for on p. 9 he asks : " If a body be acted upon 

 by no force, why should it move at all ? " 



On p. 1 1 we learn how axial rotation originates when a 

 nebular mass revolves orbitally about a centre of force. 

 The explanation depends on the different orbital motion 

 of the nearer and further parts of the nebular planet. As 

 far as this goes it should, when properly applied, give us 



