TWO TEXT-BOOKS 2.37 



together a large amount of information. The first part, occupying 

 nearly two-thirds of the whole, supplies a good elementary account of 

 the structure of a plant and its parts, and of its functions. An 

 excellent little introduction is afforded by the story of the life- 

 history of the Dandelion. The second part deals with classification, 

 and, as often happens in general text-books, the author has collected 

 a great many facts within a small compass. Occasionally Prof. Small 

 would seem to go beyond the needs of the elementary student — his 

 comparatively long discussion of phyllotaxis and the introduction of 

 the spiral is a case in point ; and parental affection could wot resist 

 the introduction of the family tree of the Compositse — but we are 

 sorry for the student ! There are three brief appendixes ; the first 

 deals with the diagnostic characters of certain medicinal or poisonous 

 plants ; the second supplies a scheme for the technical description of 

 a flowering plant ; and the third gives tests for tissues and various 

 plant substances with brief directions for staining. 



Mr. Ballard's work is intended for beginners, and is an intro- 

 duction to the study of plant-structure with the aid of the microscope. 

 It forms a suggestive course for a teacher. The author describes in 

 some detail general methods of preparation and mounting of speci- 

 mens, including the use of the microtome ; this is followed by a 

 chapter explanatory of the microscope and its use. The chemical 

 properties of cell-walls and cell-contents are then considered, and 

 a chapter follows on the use of stains. The remaining chapters deal 

 with the chief characters of the plant-cell, of the various tissues, and 

 of the structure of the principal plant organs. The subject-matter 

 is concise and the book is very clearly printed. The illustrations, 

 most of which are original, are somewhat crude but quite clear. 



A. B. R. 



Germination in its Electrical Aspect. By E. A. Baines. Pp. xx + 

 185 ; with 130 text-figures. 12s. Gd. net. Routledge : London, 

 1921. 



Many minor " facts " are given in this volume which require 

 revision. The author seems to regard as altogether negligible Shiro 

 Tashiro's striking demonstration of the production of carbon dioxide 

 by all dry and viable seeds. It seems advisable, however, to consider 

 his main thesis concerning germination. 



According to the author (p. 30)— "the fundamental principle 

 governing the germination of a seed is this " — the seed must become 

 in effect a Leyden jar, and receive a continuous charge of electricity 

 before it will germinate. He describes an experiment in which the 

 insulating inner membrane of several acorns was perforated (pp. 34— 

 35). Only in one case did germination occur and "it gave me a very 

 bad quarter of an hour, for .... it seemed .... to be subversive of 

 my theory of electrostatic action and to render all my work abortive." 

 He proceeds (p. 35) to explain the exception by repair of the insula- 

 tion, and says "the insulation of the seed must be intact if germina- 

 tion is to take place." From the author's record of his feelings with 



