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Plant Physiology and Ecology. 
A chapter is devoted to experimental evolution, namely to The 
Origin of New Forms. Without doubt, students should be required 
to attack this subject by the method of experiment, but the only 
experiment specifically detailed by Professor Clements should, in 
our opinion, be utilized by other authors as the way in which the 
subject should not be studied. We give the directions for the 
experiment in the author’s own words:— 
“ Experiment 58. The occurrence of new forms in nature. Make 
a careful scrutiny of the species of the flora for the purpose of 
discovering ecads, variants, mutants, and hybrids. Note the 
differences between the parents and the new forms discovered. 
Estimate the chances the new forms have of surviving, using number, 
vigor, kind of modification, etc., as a basis for this.” 
Second-year students of American Universities must be vastly 
superior to their British confreres if they are fit to be entrusted 
with “ an experiment ” of this character! Seriously, the observations 
and experiments necessary to carry out an investigation of this 
nature can only be performed by a botanist who has had many 
years’ experience of practical physiology, ecology, and taxonomy. 
The “ careful scrutiny ” necessary to establish the claims of a single 
natural ecad, variant, mutant or hybrid demands observations and 
experiments which must be carried on through more than a single 
year. Such observations and experiments are of the nature of a 
research which may fittingly be entrusted to picked advanced 
students ; but whilst we strongly desire to see a great increase in 
the number of such researches, we think that any attempt on the 
part of average second-year men to perform “experiment 58 ” would 
end in unmitigated disaster. 
The remainder of the book deals with matters which are more 
strictly ecological. After an introductory chapter on Methods of 
Studying Vegetation, there follow chapters on The Plant Formation, 
Aggregation and Migration, Competition and Ecesis, Invasion and 
Succession, and Alternation and Zonation. Professor Clements’ 
treatment of these subjects is well-known to ecologists, and the 
prevailing judgment of British ecologists at least is that his 
treatment is clear, definite and precise. However, all the author’s 
views have been previously given in his Research Methods ; and 
the raison d'etre of Plant Physiology and Ecology is that the 
methods are set out for use by students. Judged then as a students’ 
text-book, we cannot regard the work as a success, and we do not 
anticipate its general adoption in College and University classes. 
We should greatly like to see a text-book of practical ecology for 
Students; but such a text-book, if it is to be a success, must be 
