NATURE 



^01 



THURSDAY, SEPTEMBER 29, 1910. 



HISTORY OF BOTA.\'Y. 

 .1 History of Botany, 1S60-1900, being a Continuation 

 of Sachs' ''History of Botany, 1530-1860." By 

 Prof. J. Reynolds Green, F.R.s! (Oxford: Claren- 

 don Press, 1909.) Price 95. 6d. net. 

 BOTANICAL science has been fortunate in having 

 had as historian a botanist of such wide knowledge 

 and mature judgment as the late professor of botany 

 in the University of Wijrzburg. Sachs' " History of 

 Botany," which covers the period from the sixteenth 

 century up to i860, will always rank, not only as a 

 standard history of botany, but also as the model of 

 a critical study of the growth and progress of scien- 

 tific thought. Botanists will be grateful to the dele- 

 gates of the Clarendon Press for their decision to 

 arrange for the continuation of the history of botany 

 up to the close of the nineteenth century, the latter 

 half of which has witnessed such a surprising de- 

 velopment of the biological sciences under the stimulus 

 of Darwin's "Origin of Species/' published a year 

 before the date at which Sachs' " History of Botany " 

 stops. Sachs himself lays the greatest stress upon 

 the change in outlook in morphological and systematic 

 botany produced by Darwin's epoch-making work; 

 but though he frequently refers to the new conception 

 jof evolution, he does not deal in detail with the Dar- 

 winian theory of evolution, owing, no doubt, to his 

 conviction that it marked the beginning of a new era, 

 rather than the close of the period under his con- 

 sideration. 



Dr. Green, who has undertaken the honourable 

 task of continuing .Sachs' history, has therefore had, 

 .IS he recognises in his introduction, a very clear start- 

 ing point for his survev of botanical progress during 

 tlu- latter half of the nineteenth century. Vet he does 

 nut commence his history, as might have been ex- 

 pected, with an account of the Darwinian theory of 

 evolution. The fact that the publication of the 

 "Origin of Species" took place a year prior to i860, 

 the date at which Dr. Green takes up the history, 

 should not have been allowed to stand in the way of 

 his dealing fully with the subject, since it received no 

 detailed treatment in the earlier history. Even if this 

 omission is technically justifiable, one would at least 

 have expected a chapter dealing with such botanical 

 work as has confirmed, elaborated, or modified the 

 Darwinian theory of evolution. Yet Darwin's own 

 amplifications of his theory as detailed in his " Varia- 

 linn of Animals and Plants under Domestication," 

 published in 1S68, are not recorded, nor is the theory 

 of pangenesis, put forward by Darwin in 1868, and 

 elaborated by De Vries, either mentioned or criticised. 

 One cannot help feeling that the omission of all dis- 

 cussion of the theory of evolution is a serious blemish 

 to this history of botany. It would indeed have been 

 legitimate to have included a consideration of the work 

 of Weismann and other zoologists who have contri- 

 buted to the establishment of the theory of evolution. 

 Some discussion, it is true, bearing on evolutionary 

 NO. 2135, VOL. 84] 



principles is to be found in the chapters dealing with 

 the morphology of plants, but the importance of the 

 subject warrants a more special treatment. 



In general. Dr. Green has adhered to the lines on 

 which Sachs founded the original work, and com- 

 mences with a consideration of the advances in our 

 knowledge of the morphology of plants. "In the first 

 chapter, dealing with the nature of the alternation of 

 generations, he discusses the classic work of Hof- 

 meister, who first clearly established the homologies 

 in the various groups of the Archegoniatae, and formu- 

 lated the theory of the alternation of generations 

 obtaining in these plants. Then follows a careful and 

 critical account of the later and divergent views as 

 to the antithetic or homologous nature of these alter- 

 nating generations, a divergence of opinion which 

 continues to the present time. Dr. Green gives us 

 also an excellent and impartial summary of the oppos- 

 ing views on morphology, on one hand the school 

 of organographers led by Goebel, which considers that 

 physiological requirement is the main factor affecting 

 changes of structure, while the rival school of 

 Naegeli and Celakovsky attributes differentiation to 

 some inherent tendency of the protoplasm to develop 

 in the direction of increasing complexity. In this field 

 of thought, too, the close of the century found active 

 difference of opinion. The difliculties, on the other 

 hand, which had arisen with regard to the proper 

 interpretation of the flower were, as is shown in the 

 chapter on the morphology of the flower, largely over- 

 come by the general acceptance of Goebel 's view of 

 the independent morphological value of the sporan- 

 gium. 



To the chapter on taxonomy is added a brief account 

 of the various Floras published during the latter half 

 of the nineteenth century, but this somewhat cursory 

 treatment of the subject of geographical distribution 

 of plants as an annex to systematic botany does not 

 do justice either to the general importance from an 

 evolutionary point of view of the distribution of 

 plants, nor does it allow of an adequate consideration 

 of the physiological and ecological bearing of the 

 more recent work on plant geography. The publica- 

 tion of the " Origin of Species," it has been said, 

 "placed botanical geography on an entirely new- 

 basis," yet no one would gather this from the meagre 

 treatment accorded it in this new history of botany. 

 Sir Joseph Hooker's great memoir on the " Distribu- 

 tion of .\rctic Plants " is dismissed in two lines, and 

 yet, in conjunction with his " Introductory Essay to 

 the Flora of Tasmania," it probably did more than 

 any other publication to win the support of botanists 

 for the Darwinian theory of evolution. The total 

 omission of any mention of Warming's "Ecology of 

 Plants" and of Schimper's "Plant Geography on 

 Physiological Basis," which represent the trend of 

 modern studies in plant distribution, seems most un- 

 fortunate.. It is equally regrettable that the series of 

 monographs which have appeared in Engler's " Jahr- 

 bucher " and the important work of Drude on plant 

 geography have been left out of consideration. 



An interesting feature of the history is the inclusion 



O 



