BOTANICAL GAZETTE. 97 



this important and excellent vvork we give a running summary of its 

 contents. -Part I contains 12 chapters; the subject of Chapter I be- 

 ing Protoplasm ; Chapter II treats of the Plant-Cell; Clmpter III, 

 Cell Wall ; Chapter IV, the Formation of New Cells; Chapter V, 

 the Products of the Cell, such as chlorophyll, starch, aleurone and 

 crystalloids, crystals in cells, cell-sap, oils, resins, etc. ; Chapter VI, 

 Tissues, taking up first the various aggregations of cells, then the 

 seven principal tissues, and last the primary meristem ; Chapter VII, 

 the Tissue Systems, the sections being the Differentiation of Tissues 

 into .Systems, the Epidermal System of Tissues, the Pibro Vascu- 

 lar System of Tissues, the Fundamental System ; Chapter VIII, 

 Intercellular Spaces, and Secretion Reservoirs; Chapter IX, the 

 Plant Body, treating of (Generalized Forms, Stems, Leaves in General, 

 Arrangement of Leaves, Internal Structure of Leaves, Roots of Plants ; 

 Chapter X, the Chemical Constituents of Plants, considering Water 

 in the Plant, Soluti(>ns and Plant Food ; Chapter XI, the Chemical 

 Processes in the Plant, such as assimilation and metastasis ; Chapter 

 XII, the Relations of Plants to External Agents, as temperature, 

 light, gravitation, etc. 



Part II begins with chapter XIII upon classification; Chapter 

 XIV considers the Protophyta; Chapter XV, the Zygosporeae ; Chap- 

 ter XVI, the Oosporeae ; Chajjter XVII, the Carposporejie ; Chapter 

 XVIII, Bryophyta; Chapter XIX, the Pteridophyta ; Chapter XX, 

 the Phanerogamia ; Chapter XXI is devoted to some concluding re- 

 marks upon the number of species of plants, the affinities of the 

 groups of plants, and the distribution of plants in time. 



Of necessity the work could not be enti.ely or even mostly orig- 

 inal, but rather in Part I a following of that done in the (German labora 

 tories and based chiefly upon Sachs' great "Lehrbuch." In Part II 

 the higher plants of course conform to the system of Bentham and 

 Hooker. The classification and treatment of the lower plants seem 

 to be the author's own work and is probably the part of the book 

 that is most original. Part I would at once strike one as a smiplified 

 edition of Sachs, for many of his plates are there, and how could it be 

 otherwise, for there are no better. One naturally first turns to those 

 subjects in which he is especially interested and passes his judgment 

 upon a wi>ri< by what he reads there. Of course this is hardly fair, 

 but it is natural. As the writer has been engaged in investigating the 

 development of the embryo-sac, that subject was naturally looked into 

 first. And, in passing, wemiist most heartily commend the excellent 

 indexes which make it a pleasure 10 look up any topic. It seemed to 

 us that Vesque's work in the development of the embryo-sac had been 

 neglected, and the subject was left either in the most uncertain lighter 

 with the old idea of the embryo-sac being nothing but an enlarged 

 cell of the nucleus. A careful series of investigations by the writer 

 has confirmed the most important of Vesque's conclusions, and it 

 seems to us that the development of the embryo-sac, with its beauti- 

 ful division of labor would be interesting to any student. The notion 

 that the embryonal vescicle does not originate in what is to become 



