62 



NATURE 



[May 27, 1875 



SACHS'S « TEXT-BOOK OF BOTANY'' 



Text-book of Botany, Morphological and Physiological. 

 By Julius Sachs, Professor of Botany in the University 

 of Wiirzburg. Translated and annotated by Alfred 

 W. Bennett, M.A., B.Sc, F.L.S., assisted by W. T. 

 Tbiselton Dyer, M.A., B.Sc, F.L.S. (Oxford : at the 

 Clarendon Press, 1875.) 



IN 1868 the first edition of Dr. Sachs's " Lehrbuch der 

 Botanik" appeared in Germany; a second edition 

 was soon called for, and it appeared "in 1870 ; the third 

 was published in 1873, and the fourth was issued about 

 the end of 1874. The third edition was translated into 

 French and annotated by M. Ph. van Tieghem, and now 

 we have an English translation of the same edition from 

 the hands of Messrs. Bennett and Dyer. 



The want of a good text-book of Botany, one that would 

 give an accurate idea of the present state of botanical 

 science, has long been felt by English students. We 

 therefore heartily welcome the appearance of the English 

 translation of Sachs's " Lehrbuch der Botanik," because 

 we feel certain that it will supply that want so long felt, 

 and be of the greatest value to both teachers and students. 

 Our text-books had mostly fallen behind the time, the 

 older ideas and theories were still retained instead of 

 being swept away to make room for new facts or for the 

 more correct interpretation of long-known but imperfectly 

 understood phenomena. The illustrations of the older 

 works were often defective, frequently absolutely incoirect, 

 and yet they descended from text-book to text-book with 

 unfailing regularity. Terms were multiplied needlessly, 

 without any correct appreciation of the facts to be indicated 

 by them ; lectures became a mere illustrated botanical 

 glossary, the biology and physiology of plants were almost 

 entirely neglected, and the science rendered as repulsive 

 as possible. In the work now before us we have a text- 

 book of Botany which the teacher can confidently recom- 

 mend to the student as being an excellent guide; as 

 giving an extensive and trustworthy account of the pre- 

 sent state of botanical science in Europe ; and while it 

 indicates the theories and problems at present occupying 

 the attention of botanists, it points him to the subjects 

 which will best repay the original investigator. The 

 illustrations form an important feature in the work, most 

 of them being original, and the result of laborious investi- 

 gation : if borrowed, it was only when the objects were 

 inacessible, or because it seemed impossible to give a 

 better than the figure already in use. This gives a fresh- 

 ness to the book, which is a charm in a text-book of 

 Botany. 



Prof. Sachs's work is devoted exclusively to Morpho- 

 logical and Physiological Botany, and therefore differs 

 in its scope from the text-books to which botanical 

 students in this country are accustomed. The whole 

 work is divided into three books. Books I. and II. treat 

 respectively of General and Special Morphology, Book III. 

 being devoted to Physiology. No exhaustive account of 

 the characters of the natural orders of flowering plants is 

 given, a feature which at once places Sachs's text- book in 

 marked contrast to our English ones. All that is given 

 is an enumeration of the orders and families according to 

 the systems recently proposed by Braun and Hanstein. 

 But the want of characters of orders and families cannot 



be felt by the English student, as he can consult the 

 admirable translation of Le Maout and Decaisne's 

 " Traitd General de Botanique," and there get all he can 

 possibly want. Indeed, we may look upon Sachs and Le 

 Maout and Decaisne as forming a complete work, the 

 one treating fully of such parts of botany as are omitted 

 or only very imperfectly dwelt upon by the other. 



The General Morphology of Plants is treated of by 

 Sachs in the three chapters forming the first book. The 

 first chapter deals entirely with the morphology of the 

 cell, and is a most exhaustive treatise on the subject. In 

 describing the nature of the cell, Sachs says : " By far the 

 largest proportion of cells in the living succulent parts of 

 plants, e.g. young roots, leaves, internodes, fruits, are seen 

 to be made up of three concentrically-disposed layers ; 

 firstly, an outer skin, firm and elastic, the cell-membrane 

 or cell-wall, consisting of a substance peculiar to itself, 

 which we call cellulose. Close up to the inner side of 

 this entirely closed membrane is a second layer, also 

 entirely closed, the substance of which is soft and in- 

 elastic, and always contains albuminous matter ; H. von 

 Mohl, who first discovered this substance, gave it the very 

 distinctive appellation of Protoplasm. In the condition 

 of cells now under consideration it forms a sac enclosed 

 by the cell-wall, in which usually also other portions of 

 protoplasm are present in the form of plates and threads. 

 Absent from some of the lowest organisms, but present in 

 all the higher plants without exception, there lies im- 

 bedded in the protoplasm a roundish body, the substance 

 of which is very similar to that of the protoplasm — the 

 nucleus. The cavity enclosed by the protoplasm sac is 

 filled with a watery fluid, the cell-sap. And besides this, 

 there are also very commonly found in the interior of the 

 cell granular bodies, which, however, may be passed over 

 for the moment." Following this we have an account of 

 the formation of cells, and then the cell-wall, the proto- 

 plasm, nucleus, granular and other substances contained 

 in the protoplasm, cell-sap and crystals are each de- 

 scribed in turn. The union of cells to form tissues is 

 next described, and Sachs gives us a three-fold division of 

 tissues into epidermal, fibro-vascular, and fundamental 

 or "ground tissue." The section devoted to Primary 

 Meristem and the apical cell will be read with interest, 

 and the facts there stated will probably be new to most 

 English readers. 



The Morphology of the External Conformation of Plants 

 is treated of in the last chapter of the first book. In 

 English text-books much space is devoted to " Organo- 

 graphy," the physiological method of study being chiefly 

 adopted. Sachs, however, draws a wide distinction 

 between members and organs, and in the section on 

 Metamorphosis shows that all " organs " may be referred 

 to a few original forms. The original forms or morpho- 

 logical members are only five in number, viz., Thallome, 

 Caulome, Phyllome, Trichome, and Root. These members 

 do not perform any functions, but they are capable of 

 being " adapted " or metamorphosed into "organs "per- 

 forming many very dififtrent functions. Take the adap- 

 tations of a Phyllome or leaf-member as an illustration of 

 this. Sachs mentions that " the thick scales of a bulb, 

 the skin-like (not "cuticular," as given in the English 

 translation, p. 129, top line) appendages of many tubers, 

 the parts of the calyx and corolla, the stamens and 



