962 
their comparatively recent migration into the 
greater part of their present territory. The 
Dwarfs he considers anthropologically con- 
nected with the older inhabitants of the land 
and with the southern light stocks. The maps 
show, the one the limits of the civilizations of 
Africa, the other the localization of its numerous 
stocks. They are carefully drawn and useful. 
The publication of the English version of 
this standard work should stimulate the study 
of this important branch of science. Though 
too large for a text-book, as a work of reference 
it should be in every educational library. 
D. G. BRINTON. 
UNIVERSITY OF PENNSYLVANIA. 
Bau und Leben unserer Waldbdéume (Structure 
and Life of our Forest Trees). By Dr. M. 
BuscEen, Professor at the Forest Academy 
at Eisenach. Jena, Gustav Fischer. 1897. 
8vo. Pp. 230. 
This timely book fills a long-felt want and is, 
we believe, the first and only publication in any 
language which has ever attempted separately 
and in extenso and yet concisely to bring to- 
gether all our knowledge of the structure and 
physiology of this most important group of 
plants; R. Hartig’s and J. C. Muller’s Hand- 
books coming next to such an attempt. This 
book deals, as the title indicates, with the 
arboreal forms of Germany ; but as these are 
typical of all temperate zones, and the discus- 
sion is of general laws and does not refer 
to any particular species, it covers our own 
needs in this field. It is written, as the pref- 
ace states, ‘‘ to facilitate orientation for botan- 
ists and foresters and for all those non-profes- 
sionals who desire to obtain an insight into the 
life and working of our forests.”’ 
From this we should not, however, antici- 
pate that the subject has been treated in that 
‘popular’ method of presentation which is 
characterized by lack of thoroughness and an 
attempt to please by selection rather than to 
instruct fully. On the contrary, the book is 
written in a thoroughly scientific spirit, with due 
regard to completeness and to the relative im- 
portance of the various parts of the subject, 
albeit here and there treated somewhat scantily. 
The author, formerly professor at the Uni- 
SCIENCE. 
[N.S. Vou. VI. No. 156. 
versity of Jena, has evidently brought to his; 
task not only a thorough knowledge of the 
literature on the subject, at least the German 
and French, to which he closely and copiously 
refers in all particulars, but has compiled the 
facts with critical judgment. 
Having been accustomed by his position to 
present the subject to a class of students who 
are trained to make practical use of the same 
in their professional pursuits, he has known how 
to lay most weight on the essentials from that 
point of view. If we add that the diction is 
simple and the literary style pleasing, we have 
given all the points that make a good and 
useful book. Even the usual deficiency of 
German books, the absence of a full index, is, 
in part at least, overcome by a ‘register of 
matters not readily to be found through the 
table of contents.’ How very deficient this 
register is may be illustrated by one example: 
Although in the chapter on causes of tree form, 
under the caption ‘ The Wind,’ frost phenomena 
of arctic regions are discussed—and nowhere 
else—the index contains no reference under 
‘frost,’ and certainly the table of contents 
would hardly lead one to the place. The 
disposition of the material appears often not 
very logical and hence an index is so much 
the more desirable. 
Lack of space forbids us to. go into a critical 
review in detail. We may only give an idea of 
the contents by giving titles of chapters. ‘The 
Winter Aspect of Trees’ is the title of the first, 
followed by ‘Causes of Tree Form’ as the 
second chapter. These two chapters could, 
with the aid of N. J. ©. Muller’s painstaking— 
unfortunately much overlooked—work have 
been profitably enlarged. The chapter on 
‘Buds’ is followed by 75 pages devoted to the 
body of the tree in six chapters, discussing the 
‘character and functions of the formative tissues 
of the tree,’ ‘the elements of the woody tissue’ 
and ‘the bark,’ the ‘annual ring,’ ‘structure 
and weight of wood and heartwood formation.’ 
The ‘ foliage’ and ‘the root’ have each a large 
chapter devoted to them. © 
In the chapter on the ‘ Water Supply of the 
Tree’ we note a curious misconception of an 
interesting experiment of Strasburger’s, into 
which the great experimenter himself seems to 
