ZOOLOGY AND BOTANY, MICROSCOPY, ETC. !^9 



Structure and Development. 

 Vegetative and Reproductive. 



Methods in Plant Histology." — The present issue is the third 

 revised edition of the original work, which appeared in 1901 ; the 

 second edition was published in 1905. The book is well-known in 

 botanical laboratories, and the latest version renders it an up-to-date 

 handbook for the practical student of the minute structure of plants. 

 During the past ten years methods have become more and more exact, 

 and their exhaustive treatment renders the present volume practically 

 a new book. Great improvements have been made in the paraffin 

 method, so that sections are easily cut which were impossible ten years 

 ago, and ten years of further experience with the Venetian turpentine 

 method have made it possible to desci'ibe it with greatly increased 

 detiniteness. The subject-matter is divided into two parts. The first 

 contains a description of apparatus, reagents for killing, fixing, clearing, 

 etc., the various stains, and general remarks on staining and mounting. 

 The different methods — freehand, glycerin, Venetian turpentine, paraffin 

 and celloidin — are described in detail, and there is a chapter on special 

 methods for various special cases. A chapter has been added on 

 photomicrograph and lantern slides. The second part consists of specific 

 directions for applying the methods described in the first part to a 

 selected series of forms representing the various plant-groups from 

 mycetozoa and algaj up to angiosperms. Helpful directions are given 

 for collecting and growing laboratory material. There is a chapter on 

 using the Microscope, and one describing a class list of preparations 

 suitable for a student's course. Many of the illustrations are photo- 

 micrographic reproductions. 



Vascular Anatomy of the Megasporophylls of Conifers.f — Hannah 

 C. Aase, as a result of the study of the origin and course of the vascular 

 bundles which supply the sporophylls and tracts in a representative 

 series of genera and species, tabulates the following conclusions : — Two 

 general tendencies are apparent in the evolution of the ovulate strobilus, 

 namely, the reduction in number of sporophylls and the modification of 

 a compound into an apparently simple sporophyll ; the latter generally 

 implies loss of one of the two parts of the sporophyll or their union. 

 Reduction has reached its highest expression in members of the C^ipres- 

 sineae, Taxineit and Podocarpinese ; one type of reduction is represented 

 by the general sterilization and reduction of parts in the lower sporo- 

 phylls of Pinus. Simplification of a compound sporophyll is most fully 

 realized in Art hrot axis selaginoides, Affathis and Saxegothsea ; an exten- 

 sive reduction of the bract occurs in Cedrm and the lower sporophylls 

 of Finns maritima ; the scale in Fht/Uocladus is probably reduced so as 

 to be represented only by a distinct ovular supply ; the union of the 



* By Charles J. Chamberlain, pp. xi and 314 (107 figs.). University of Chicago 

 Press ; published in the United Kingdom by the Cambridge University Press, 

 London. 



t Bot. Gaz.,lx. (1915) pp. 277-313 (figs.). 



