Nov. 22, 1888] 



NATURE 



•5 



^till a new book. In preparing the new edition, Prof. 

 Bower has no longer had the active co-operation of Dr. 

 Vines ; though, as explained in the preface, the chapters 

 originally contributed by the latter have been almost 

 entirely embodied in the present work. A short account 

 of the book as it now stands may be of service to the 

 readers of Nature, for as compared with the former 

 edition it has undergone considerable rearrangement and 

 extension. In both these respects the first three chapters, 

 which are introductory to the study of the. types, show 

 important changes. The book begins with a list of 

 apparatus, and of the more ordinary reagents, the mode 

 of preparation of which is described. A more detailed 

 list of reagents is now given in the first of the new 

 appendices at the end of the volume. 



Chapter I. deals with the making of preparations, and 

 the adjustment of the microscope. Under both heads the 

 directions are most practical and excellent, and cannot 

 be too strongly commended to the attention of students. 

 This chapter is essentially elementary ; and only simple 

 methods, such as are indispensable for all workers, are 

 included. A very clear account of section-cutting is 

 ■iven, and in Fig. i a diagram is added in order to 

 <plain the meaning of "radial" and "tangential" 

 cctions, a point which is often puzzling to beginners. 

 The introduction of diagrams is an important feature of 

 the new edition. Though not very numerous (fifteen in 

 all) they will be found a very useful help. Strictly dia- 

 grammatic figures have been used in all cases, in order 

 that the student may not be tempted to make use of the 

 illustrations as substitutes for the objects illustrated. 

 The first chapter concludes with instructions on drawing 

 from the microscope, and on measurement. ^ - ' 



Chapter II. contains a number of " practical exercises." 

 In the first of these the microscopic examination of the 

 pulp of an apple serves to make the student acquainted 

 ■with the general characteristics of vegetable cells.^ The 

 next exercise is on Spirogyra, and the third on the Fern- 

 prothallus. A reference to the general account of the 

 prothallus at p. 300 would here be useful to the beginner. 

 Next comes the Beet- root, the first object of which 

 sections have to be made. Here the chief osmotic phe- 

 nomena are studied. Protoplasmic movements are illus- 

 trated by Trianea or Hydrocharis, and by- Tradescantia. 

 The last exercise (in small print) is on cell-division, as 

 shown in the staminal hairs of Tradescantia. This, we 

 think, would have been better omitted at this place. It is 

 impossible in a {&\s lines to give a satisfactory account of 

 so complicated a process, and inaccuracies can scarcely 

 be avoided. Thus the statement that the nuclear 

 ^' fibres are ruptured in the equatorial plane " cannot be 

 accepted in the light of our present knowledge. 



The third chapter, headed " Micro-chemical Reactions," 

 gives a series of further practical exercises of a more 

 advanced character. These are only in part designed for 

 the beginner, and those which he is intended to work 

 through are indicated by a marginal line. The remaining 

 parts of the chapter are designed to be used for purposes 

 •of reference, during the subsequent investigation of the 

 types. The improved account of the chlorophyll-grains 

 ^p. 51) and the fuller description of vegetable oils (p. 59) 



' A misprint on p. 27 (line 4) may be noticed, where the word "as" has 

 keen omitted. 



may be especially noticed. Into this chapter an adequate 

 account of the chief facts relating to the division of the 

 cell and nucleus might perhaps have been introduced 

 with advantage, as their satisfactory observation with the 

 help of modern methods is by no means beyond the 

 powers of the more advanced students. 



The introductory portion of the work terminates with 

 some useful remarks on staining, clearing, and permanent 

 mounting (pp. 65-70). 



The study of the Dicotyledonous types begins with 

 an examination of the seed and embryo in the Bean, the 

 Cucumber, the Sunflower, the Castor-oil plant, and the 

 Marvel of Peru. In the reviewer's opinion it would have 

 been better to begin at once with the seedling, as the 

 structure of the seed cannot possibly be really understood 

 until the reproductive organs have been investigated. 

 This especially applies to the last example cited, namely, 

 Mirabilis, the description of which will, we fear, be found 

 very puzzling by the student. 



The main outlines of the description of types remain 

 as in the former edition. Only a few of the chief altera- 

 tions need be mentioned. Two excellent diagrams of 

 bundle-systems (after Reinke) are introduced at pp. 79 

 and 81, while the investigation of the seedling Sunflower 

 by means of successive transverse sections is a most 

 valuable addition to the treatment of the difficult subject 

 of the distribution of vascular bundles. Attention may be 

 called to the remark, on p. 95, that the work on \h.Q young 

 stem of the Sunflower may with advantage be taken earlier; 

 The structure of the stem before secondary thickening has 

 begun must certainly be understood in order that the 

 subsequent changes may be intelligently studied. Dia- 

 grams, after Sachs, are introduced at p. 98 to illustrate 

 the origin of the cambium, and at pp. 100 and 102 to 

 show the arrangement of the cells at the apex of the 

 stem. In the account of the periderm (p. 107) the 

 terminology has been revised, and now agrees with 

 that of De Bary. This subject is now illustrated by 

 diagrams. These are original, and so also are those on 

 p. 122, by which the form of cambial cells is explained. 



At p. 137, the intercellular space beneath the stoma is 

 still called the " respiratory cavity." This term, though 

 so generally used, is likely to mislead beginners as to the 

 function of the stomata, and the colourless phrase, " air- 

 chamber," seems preferable. To the account of the struc- 

 ture of the petiole, a description of the pulvinus in the 

 French Bean is now added. The Holly has been substi- 

 tuted for the Cherry- Laurel as the type of a coriaceous 

 bifacial leaf ; while, as examples of " iso-bilateral " struc- 

 ture, the phyllodes of Acacia, and the leaves of Eucalyptus 

 globulus, are introduced. The aquatic type of leaf is well 

 illustrated by Hippuris, in which the sub-aerial and the 

 submerged leaves are compared. Passing by several 

 minor additions, the valuable new section on the fall of 

 the leaf may be especially noted. An account of hairs 

 and emergences has also been added, in small type. 



The work on the root of Dicotyledons has been ex- 

 panded, and the very clear original diagram of its 

 transverse section, before and after secondary thickening, 

 is likely to be of great service. 



The stem of the Monocotyledons is now described in 

 two additional types— the Hyacinth, as a bulbous plant, 

 and Elodea, as an aquatic. The last-named plant is also 



