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the work was published in German as long ago as 1898, but the subject- 

 matter has been brought thoroughly up to date in an appendix of 

 218 pages, and the " Schlussbemerkungen " of the German edition have 

 been revised and extended in the "Concluding Remarks" (pp. 1070-1168), 

 where a very full review of those anatomical characters which have proved 

 to be of taxonomic value is given. The general plan of the work is to 

 deal with each of the Dicotyledonous families in turn, and to pass in 

 review the anatomical features which characterize it, and then to deal 

 with the structure of the leaf and stem in detail. At the conclusion of 

 each section a list of the works relating to the family is given. The 

 completeness and comprehensiveness of such a mass of minute detail can, 

 of course, only be tested by the continued use of the book. Its trans- 

 lation has sometimes involved the difficulty of finding a term which will 

 accurately convey the author's meaning, but this difficulty has, to a large 

 extent, been met by the making of a glossary, which also serves as 

 a partial index. It is a pity that a fuller index could not have been 

 given, as it would have rendered the book much more easy to consult. 

 One hundred and eighty-nine figures illustrate the text, and the print and 

 paper as usual leave nothing to be desired. 



" The Origin of a Land Flora." By Professor F. 0. Bower, F.R.S. 

 8vo., 727 pp. (Macmillan, London, 1908.) 18s. net. 



The learned author has for many years applied himself to the close 

 study of those groups of plants, the mosses and ferns and their allies, 

 which appear to come between the primitive alga? and the highly complex 

 seed-bearing plants of to-day. In the present volume he has brought 

 together the facts he has accumulated, and the discoveries of other 

 investigators in the same group, and reviewed them in the light of our 

 present knowledge of the sequence of evolution among plants as revealed 

 in the rocks, with the object of formulating a theory of the origin of the 

 habit which all the higher plants have acquired of living on the land. He 

 has produced a work full of details, marshalled, arranged and discussed 

 with all that philosophical acumen which we have learned to look for in 

 the works of the German botanist, and but rarely in those of any other 

 nation. 



The title of the book might lead one to suppose that here was one 

 suitable for the general reader, but the sub-title, " A Theory based upon 

 the Facts of Alternation," would prepare him for an abstruse discussion. 

 Indeed, only the specialist could hope to follow many of the arguments 

 brought forward from so many lines of research, all, the author considers, 

 pointing to the conclusion that the land flora had its origin in "a phase 

 interpolated between the events of chromosome-doubling and chromosome- 

 reduction in the primitive life-cycle of plants of aquatic habit." 



" The final goal of all organic development is the establishment of 

 new individuals," and if the land flora had its origin in this way, and 

 development followed the lines sketched by Professor Bower, then it is 

 intensely interesting to see how that in the earlier forms of land plants 

 (some of which have persisted, in a modified form perhaps, to the present 

 day) when the method of ensuring the production of adaptable individuals 

 and their establishment was not greatly specialized, this deficiency was 



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