Bihh'ofjrnpJu'cal Noticeft. 329 



that the author is capable of doing good service to biological science 

 as a thinker under more favourable conditions than those imposed by 

 University Extension lecturing. As a specimen of judicious treat- 

 ment we may refer to the summing-up of the cell-theory in the 

 chapter oq " The Elements of Structure '' (p. 1 83) : — 



" We study the nucleus, first as a simple unit which divides, years 

 afterwards as composed of a network or coil of nuclear threads which 

 seem ever to become more and more marvellous, ' behaving like little 

 organisms.' We split these up into ' microsomata ' and so on, and so on. 

 But we do not catrh the life of the cell, we cannot locate it, we cannot 

 give an account of the mechanics of cell-division. It is a mvstery of 

 life. After all our analysis we have to confess that the cell, or the proto- 

 plasm, or the archoplasiu, or the cliromatin threads of the nucleus, or the 

 'microsomata' wliich compose them b.iffle our analysis ; they behave as 

 they do because they are alive." 



The tabular summaries, such as those showing the characteristics 

 of animals and plants (p. 170), the survey of the animal kingdom 

 (p. 272), the tree of life (p. 12), the summary of evolution theories 

 (p. 302), &c. are also worthy of commendation. 



As a fair average sample of the author's method we give the 

 following extract from his treatment of the resemblances aud differ- 

 ences between animals and plants (p. 171): — • 



" The net result of this contrast is that animals are more active than 

 plants. Life J umbers in the plant; it wakes and works in the animal. 

 The changes associated with the living matter of an animal are seemingly 

 more intense ;md rapid ; the ratio of disruptive power-expending chan<j-es 

 to constructive power-accmnulatiug changes is greater ; most animals 

 live m jre nearly up to their income than most plants do. They live on 

 richer food ; they take the pounds which plants have accumulated in 

 pence, and spend them. Of course plants also expend energv, but for the 

 most part within their own bodies ; they neither toil nor spin. They 

 stoop to conquer the elements of the inorganic world, but have comjmra- 

 tively little power of moving or feeling. They are more conservative and 

 miserly than the liberally spendthrift animals, aud it is possible that some 

 of the most characteristic possessions of plants, e. (j. cellulose, mav be 

 chemical expressions of a marked preponderance of coustruetive and "up- 

 building vital processes. It is enough, however, if we have to some 

 extent re.dized the commonplaces that plants and animals live the same 

 sort of life, but that the animals are on an averag- more active and wide- 

 awake than the plants." 



We have already pointed out the general raeagreness of the treat- 

 ment given to the different portions of the work, necessitated by the 

 compression of a very wide subject into a very small compass. An 

 example will serve to indicate the defect to which we allude. 

 Chapter IX. is headed " The Divided Labours of the Eody." As 

 subheadings appear the following : — 1 . Division of Labour. 2. The 

 Functions of the Body : Movement ; Nutrition ; Digestion ; Absorp- 

 tion ; The Work of the Liver and the Kidneys ; Respiration ; Circu- 

 lation ; The Changes within the Cells ; The Activities of the Nervous 

 System. 3. Sketch of Psychology. 



