May 16, 1912] 
NATURE 
265 
ferent parts of the world. In his scene-painting the 
author shows an alert mind, in which the memory 
of his own travels and the knowledge that he has 
industriously acquired from direct observation and 
from books are ingeniously blended together. 
In his own special line—that of describing the 
association and interaction of animals against a 
suitable background—Dr. Renshaw displays a 
notable gift, and his heart is in the work of attract- 
ing his readers to that which he himself finds so 
absorbing. The vividness, the fullness, the tense- 
ness of tropic nature are ever in his mind, but the 
attempts to depict them would have been more 
successful had more restraint been exerted. “ War 
to the adjective” might well be his motto. The 
gory element is certainly too obtrusive for most 
readers’ tastes, and we could well have spared 
some of the tales of blood and fury which end in 
clouds of flies. However, the careful observation 
and the attractive illustrations make amends, and 
we can confidently recommend this volume to all 
who have found the earlier works by Dr. Renshaw 
a stimulating account of moving incidents by flood 
and field. 
(4) This book differs from all other text-books | 
of biology with which we are acquainted in de- 
scribing organisms from the point of view of 
experimental morphology; that is to say, it takes 
for granted a knowledge of general anatomy, 
physiology, and classification, and proceeds to 
show what factors are at work in the production 
and maintenance of form and of structure. From 
the modernity of its point of view and its wide 
scope, this work goes far to provide what is so 
greatly needed—a really biological text-book; and 
it is only the immense and increasing amount of 
material and the rapid changes of knowledge in- 
volved thereby, that have prevented the authors 
from effecting a still more intimate association | 
between the factors that govern the zoological side 
of the problem and those that condition the botani- 
cal one. 
The book consists of three parts, which are 
severally the work of distinguished biologists. 
Prof. Nussbaum, of Bonn University, has written 
the opening section, and deals with that special 
aspect of experimental animal morphology which 
presents itself upon consideration of the regenera- 
tive and regulatory processes in animal tissues; 
Prof. Karsten deals in the second section with the 
ecology of plants; and Prof. Max Weber has 
written the concluding part upon the factors of 
animal life. From the student’s point of view, the 
middle section should have come first, since it is 
not only simpler in its subject, but also because it 
is written in a more simple manner. For the 
same reasons the chapter on animal biology should 
NO. 2220, VOL. 89] 
have preceded Nussbaum’s section on special 
problems. The order, however, is of comparatively 
little importance to those who wish to consult 
rather than to read the work consecutively. 
On their several topics these writers are indis- 
putable authorities, and write out of the fullness 
| of their knowledge and experience. The result is 
a work of unusual value. 
PLANT PHYSIOLOGY FOR AGRICULTURAL 
STUDENTS, ~ 
Plant Physiology, with special reference to Plant 
Production. By Prof. B. M. Duggar. Pp. xv+ 
516. (New York: The Macmillan Company.; 
London: Macmillan and Co., Ltd., 1911.) Price 
zs. net. (The Rural Text-Book Series. Edited 
by L. H. Bailey.) 
« LANT physiology,” the author states in his 
preface, ‘‘finds its practical application in 
plant production. . . . It is somewhat strange, 
therefore, to find that as a separate course plant 
physiology is not yet offered in some of the col- 
leges whose purpose is primarily to train persons 
for practical or rural pursuits.” In helping to 
remedy this state of affairs, the author has pro- 
duced a very readable book, useful to the student 
whose life is to be passed among plants and 
whose living is to be got out of them, and at the 
same time interesting to the general reader who 
loves his garden and has an appreciative eye for 
flowers and trees. 
That the book is American goes without saying ; 
the large proportion of our modern books for 
agricultural students comes from the States. Its 
distinguishing feature is that at every turn it 
brings in such practical applications of particular 
| facts or principles as have been made, thus empha- 
sising the economic importance of the subject while 
_ adding considerably to the interest. The general 
plan of the book is as follows :—After a descrip- 
tion on the usual lines of the plant cell, the student 
is led on to the water relationships of the plant, 
to the root and soil, to absorption, transpira- 
tion, and water requirements of crops; then 
to a consideration of mineral nutrients and their 
special functions and relations. The student is 
now directed to the leaf, the intake of carbon and 
the making of organic food, the assimilation of 
nitrogen and the working up of simple nitrogen 
compounds into protein, and the general pheno- 
mena of nutrition, respiration and growth. Next 
comes the discussion of seed formation and repro- 
duction. Then come three chapters that look out 
| of place, dealing respectively with the effects of 
temperature, of light, and of deleterious chemical 
| agents on plant life. Finally we get back to the 
