642 
NATURE 
[AUGUST 12, 1915 

chemicals and drugs, and those employed in 
clinical and bacteriological diagnosis and analysis. 
We find a full account of Abderhalden’s serum 
reaction, of a bacteriological examination of dis- 
tilled and drinking waters, with a table of the 
analytical results obtained, and the conclusions 
founded on them, of the various methods for per- 
forming the Wassermann reaction for syphilis, 
and of the chief advances made in bacteriological 
technique. This volume will be found invaluable 
in the chemical, bacteriological, and phar- 
maceutical laboratory. Martindale’s Extra Phar- 
macopeeia should find a place on the library shelf 
of every medical practitioner and pharmacist. 
(2) In 1904, owing to the increasing size of 
“Squire’s Companion,” it was decided to sub- 
divide the work, and to publish it in two parts, 
“Squire’s Pocket Companion” and ‘“‘Squire’s 
Companion.” ‘‘ Squire’s Pocket Companion” is 
the smaller volume, containing information on 
such matters as are commonly arising in the 
orinary course of prescribing and dispensing, and 
is written specially for the medical profession. 
This second edition of the work follows the lines 
of previous editions of the Companion, and is 
arranged in alphabetical order. The principal 
monographs are divided into distinctive headings, 
a description of the drug with its usual method 
of preparation, solubility, medicinal properties, 
dose, prescribing notes, incompatibles, official pre- 
parations, not official preparations, and antidotes. 
The solubilities of chemical substances have 
been completely revised and the medicinal proper- 
ties brought thoroughly up to date, the latest re- 
ferences being included. The doses are given in 
both the imperial and metric systems, and are 
those generally employed. The prescribing notes 
have received particular attention, and the revision 
has been very thorough and complete. 
The chapter on therapeutic agents of microbial | 
origin has been almost completely re-written by 
Prof. Hewlett; it gives full information on anti- 
toxins, serums, tuberculins, vaccines, etc. 
of British and foreign spas is included, also a thera- 
peutical classification of remedies, with a list of | 
those applicable for special ailments. A full 
general index enhances the value of the work, 
which will be found of the greatest service by the 
medical practitioner and pharmacist. 

MIND IN ANIMALS. 
The Investigation of Mind in Animals. 
Smith. Pp. xi+194. (Cambridge: At the 
University Press, 1915.) Price 3s. net. 
HIS is a book intended for the general reader 
rather than for the investigator; and, con- 
sidering its limited size, it is a very admirable 
NO. 2389, VOL. 95] 
By E. M. 
A list | 


| be studied. 
presentation of the best methods by means of 
which the problem of the nature of animal conduct 
is now being investigated. This. problem is 
primarily one for the naturalist who knows very 
intimately the habits of the organisms that are to 
Yet experimental psychology is now 
a science with well-developed methods and criteria, 
and with a technique of its own, and one cannot 
consider the multitude of instances of apparently 
intelligent behaviour in the lower animals without 
feeling that much of the lack of critical examina- 
tion of these cases is due to imperfect knowledge 
of this technique. 
the author’s short accounts of the experimental 
methods devised by Jennings, Yerkes, Thorndike, 
and others very serviceable, and the bibliography 
contains references to most of the important 
memoirs, 
The author avoids controversy and discussion as 
much as possible, and short statements of his own 
conclusions would have added to the value of the 
book. He relegates the theory of tropisms to a 
very subordinate place, refusing it that generality 
that has occasionally been claimed for it. 
Jennings’s interpretation of the apparently random 
movements of certain protozoa as based upon a 
method of trial and error is accepted, but it is 
argued that rigid determinism is nevertheless in- 
volved, although plasticity of behaviour is implied 
in Jenningss’s interpretation. The conclusion is not 
very clear. The book contains a fair account of 
the admitted phenomena of “homing” among 
birds and insects. There is a short summary. of 
| the evidence in favour of ideation in animals other 
than man; and in the last chapter the reader will 
find too short a reference to the wonderful thinking 
horse which in ten seconds found the fourth root 
of the number 456976 ! ie dle 

OUR BOOKSHELF. 
The Principles of Rural Credits as Applied in 
Europe and as Suggested for America. By 
J. B. Morman. Pp. xviii+296. (New York: 
The Macmillan Co.; London: Macmillan and 
Co., Ltd., 1915.) Price 5s. 6d. net. 
ALTHOUGH this book is written primarily with the 
idea of calling attention to the problems of credit 
as they affect farmers in the United States and 
Canada, it contains much of interest to any stu- 
dent of rural economics. The whole subject has 
been investigated recently by the United States 
Commission on Rural Credits, and the present 
volume is latgely a condensed and popularised 
version of the Commission’s reports to Congress. 
In this way the book falls naturally into two 
pu the first consists of the information col- 
ected from an exhaustive study of the systems 
of rural credit in operation in Europe; in the 
The student of biology will find, 

