February 24, 1910] 



NA TURE 



given last year by Prof. Maclaurin in the American 

 Museum of Natural History. The subject undertalven 

 was a difficult one, nameh', to treat from a non- 

 mathematical point of view, and in such a way as to 

 be understood by non-physicists, the more advanced 

 portions of the optical theory. Prof. Maclaurin has, 

 however, successfully done this. The lectures are 

 extremely clear and full of information. Among the 

 subjects dealt with are colour vision and colour photo- 

 graphy, dispersion and absorption, polarisation, inter- 

 ference and diffraction, and the connections between 

 light and electricity, such as the Zeeman effect. The 

 lectures make very good reading, and would be appre- 

 ciated even by those for whom the exclusion of mathe- 

 matics is unnecessarv. 



FUNCTIONAL PSYCHOLOGY. 



(i) Genetic Psychology. An Introduction to an 

 Objective and Genetic Vieiv of Intelligence. By 

 E. A. Kirkpatrick. Pp. xv+373. (New York : The 

 IMacmillan Company, iqog.) Price 5^. net. 



(2) The Psychology of Thinking. By Dr. J. E. 

 Miller. Pp. xxv + 303. (New York: The Mac- 

 millan Company, 1909.) Price 5$. net. 



(i) ' I ' HERE seems to be an ever-increasing 

 J- tendency among psychologists at the present 

 day to assimilate not only their methods of procedure, 

 but also the schemes of description and explanation 

 underlying their science to those emploved by biologv. 

 In place of, or, more accurately, in supplementation 

 of, the older "introspective" psychologv — including 

 "introspection under test conditions" — we now find a 

 " functional " psychology which treats of the indi- 

 vidual mind from the point of view, primarilv, of its 

 usefulness in adapting the individual to his environ- 

 ment. Both the books under consideration are written 

 from this point of view. They are, both of them, ex- 

 cellent examples of the use of the biological method. 

 Mr. Kirkpatrick tells us in his preface that all 

 psychology must be founded on genetic principles, and 

 studied in close relation to the facts and theories of 

 the other sciences of life phenomena. He himself 

 cherefore commences his book with a clearly written 

 and somewhat full account of the forms of behaviour 

 of the lower animals, together with their structural 

 bases, selecting types at different stages of evolution 

 for detailed description. Not until the middle of the 

 book does he reach the subject of consciousness "as 

 such," and even here he deals first with its objective 

 aspect, viz. its external effects and criteria, as 

 exemplified by human adult consciousness. The 

 account is excellent, and conducive to clear thinking 

 on a difficult subject. Following this, there are 

 chapters on " specific conscious states," " types of 

 adaptive activity or intelligence," " t}-pes of learning 

 activity," and "racial and individual development." 



The book should prove of very considerable value 

 to students, since it sums up a great deal of recent 

 monograph work in most clear and interesting form. 



(2) Dr. Miller's book is inspired throughout by 

 KO. 2!04, VOL. S2I 



what he aptly calls a clinical interest in the thinking 

 process as it occurs in the child's mind, in concrete 

 form, at the various stages of its education. The 

 earlier chapters are devoted to a general explanation 

 and justification of the biological point of view, and 

 form an excellent propaedeutic to the predominantly 

 pedagogical account of thinking which follows. By 

 those educationists — and they must surelv be manv — 

 who have become dissatisfied with the quasi-logical, 

 almost scholastic, account of the thinkmg process 

 given by the older school of psychologists, the author's 

 treatment of his subject will be found both stimulat- 

 ing and refreshing. Thinking is kept throughout in 

 its correct and natural close relationship with other 

 forms of mental activity and general organic 

 behaviour. Not abstract schemes, but actual concrete 

 bits of thinking, are to be found skilfully analysed 

 and classified on every page. The continuity between 

 the empirical thinking of animals and children and 

 the reasoning of the trained adult mind is well 

 brought out, together with their specific differences, 

 and throughout the entire account the author never 

 loses sight of the fundamental characteristic of the 

 life process as expressed in terms of the satisfaction 

 of needs, which is the central and controlling idea ot 

 his psychological system. The book breaks new 

 ground in its treatment of a hitherto neglected depart- 

 ment of psychology, and will undoubtedly be welcomed 

 by psychologists and educationists alike. W. B. 



OUR BOOK SHELF. 



Das Kaninchcn. Ziigleich einc Einfilhrung in die 

 Organisation der Sdugctierc. Monographien ein- 

 heimischer Tiere. Vol. ii. Pp. vi + 307. (Leipzig: 

 Dr. Werner Klinkhardt, 1909.) Price o marks. 



Following upon an industriously compiled volume 

 devoted to the frog, this series, edited by Prof. 

 Ziegler, is now represented by a work on the rabbit, 

 which we may confess at once is a disappointing 

 one. It is little more than a new edition of Krause's 

 well-known work, with a few additional illustrations. 

 Indeed, though more elaborate in detail, the treat- 

 ment is hardly so good as that of any of the elemen- 

 t.-iry treatises in wliich this familiar animal has been 

 described. There are no practical directions for 

 actual dissection, and the figures are singularly 

 devoid of explanatory lettering, an omission which 

 becomes ludicrous in the case of complicated muscu- 

 lature. The editor has not exercised sufficient control 

 in that important respect, nor in the treatment of the 

 various sections, bones and muscles being allowed 

 far too large a share in a purely descriptive work. 



The book begins well, and, in fact, the introduc- 

 tion is its saving grace. The author treats in this 

 opening section of the relation of the rabbit to its 

 congeners, the differences between rabbits and hares, 

 the various races, their habits, and history. Then 

 follows a section upon diseases and parasites, but 

 without any figures of the latter and without any 

 mention of the two commonest cestodes, Cysticercus 

 pisiforniis and Coeniirns serialis. Then follows an 

 account of how to kill the creature, and, having done 

 so, the author treats it for the whole of the rest of 

 the work as dead. The book is a studv in necrology. 

 We are not told how the rabbit breathes or digests, or 

 how it does anything. .\re there sweat-glands? The 



