THE LIVING PLANT 313 



read." He has sought especially to interpret those phenomena of 

 plant life which come within ordinary observation and experience, 

 omitting certain matters which, though of high technical interest, 

 lie outside the experience of the general observer. He is a strong 

 advocate of Darwinian adaptation, regarding causative adaptation 

 as the most rational explanation we possess of the relations of 

 living beings to their environment. While admitting that every 

 individual process of plants is purely mechanical, physical, or 

 chemical, the author assumes a vitalistic influence which holds 

 these processes in orderly sequences — what he defines as a per- 

 fectly natural vitalism based on the superior interpretative power 

 of an hypothesis assuming the existence in Nature of an X-entity, 

 additional to matter and energy but of the same cosmic rank as 

 these, and manifesting itself to our senses only through its power 

 to keep a certain quantity of matter and energy in the continuous 

 orderly ferment we call life. 



Whether or no we are entirely in agreement with Dr. Ganong's 

 premises, we must admit that he has given us a charmingly 

 written book, in which the story of the living plant is clearly and 

 attractively told. Even the titles of the chapters are translated 

 into ordinary language. Thus chapter i., on " the various ways 

 in which plants appeal to the interests and mind of man," is a 

 readable explanation of the various methods of study in the science 

 of botany, and at the same time a good exposition of the point of 

 view taken by the author. The plan of the remaining chapters, 

 seventeen in number, is as follows : The prevalence of the green 

 colour and its meaning in the life of the plant is first explained, 

 and then the general facts of the morphology and ecology of 

 leaves and stems are dealt with as the result of the need for 

 exposure to light. The work done by plants and the source 

 of their power to do it is the text of a chapter on respiration, 

 and so on. In this way the various life-processes are lucidly 

 explained. 



In later chapters pollination of flowers and dissemination of 

 fruits are dealt with. The method of origin of new species and 

 structures and the causes of their fitness to the places they live in 

 is the heading of a chapter on evolution and adaptation ; this is 

 followed by a chapter on the improvements made by man in 

 plant breeding, while a final chapter deals in a very general way 

 with the great groups into which plants fall, including the 

 ecological as well as the genealogical aspect. There are a large 

 number of excellent diagrams and figures, and the book is beauti- 

 fully printed. A R "R 



British Plant-Galls : a Classified Textbook of Cecidology. By 

 E. W. Swanton. Pp. 287 x xv. Methuen & Co., Ltd. 

 7s. Qd. net. 



All botanists on their rambles or forays have noticed the 

 curious malformations of plants which they have usually, but of 

 necessity, been content to designate " galls," except in those cases 



