October 14, 1922] 



NA TURE 



509 



European skulls hitherto. The width of the face in 

 front of the ears is 153 mm., at the angles of the lower 

 jaw 127 mm., betokening an extraordinary develop- 

 ment of the masseter muscles. Notwithstanding these 

 features, the skull is that of a strong, handsome, and 

 big-headed man. 



The opening chapters of this work are devoted to an 

 orthodox and clearly worded description of Europe in 

 the Ice-age. In dealing with human remains, Prof. 

 Werth depends very largely on the methods and con- 

 clusions of Schwalbe and of Klaatsch. Prof. Werth 

 accepts Schwalbe's verdict that Neanderthal man was 

 not the precursor of modern man, but was extinguished 

 by the arrival of the Aurignacian race in Europe. He 

 is inclined to think the Cromagnon type represents a 

 later invader of Europe, and accepts this type as the 

 precursor of the long-headed modern Europeans — both 

 of the dark Mediterranean and of the fair Scandinavian 

 tvpe. The work, of which this is Part 1, is well 

 illustrated. 



Studien an Infusorial iiber Flimmerbewegung, Loko- 

 moiion and Reizbeantwortung. Von Dr. Friedrich 

 Alverdes. (Arbeiten aus dem Gebeit der experi- 

 mentellen Biologie, Heft 3.) Pp. iv+ 130. (Berlin : 

 G<1 under Borntraeger, 1922.) 125. 



The little book under notice is a record of careful work, 

 chieflv upon the behaviour of Paramcecium caudatiiin. 

 although the three other species of Paramcecium, 

 Stentor polymorphus, and other Infusoria, figure in some 

 of the experiments. The author has made an especially 

 detailed studv of the movements of Paramcecium and 

 of the action of its cilia, and his observations on its 

 morphology are not without interest. He discusses the 

 behaviour of these organisms when operated upon, 

 and also their reactions to narcotics and other chemical 

 stimuli and to the galvanic current. 



While the author admits the merit of Jennings's work 

 in this field of study, he is, nevertheless, frequently in 

 conflict with this worker, both in his observations of 

 behaviour and his interpretations of them ; but it is 

 not certain that he thoroughly grasps Jennings's views, 

 and it is noteworthy that the latest edition of " The 

 Behaviour of the Lower Organisms " (Columbia Univ. 

 Press, 1915) is not in Dr. Alverdes's Bibliography. Dr. 

 Alverdes ranges himself energetically against all those 

 who see in the Infusoria nothing but " small automata," 

 and vigorously opposes the mechanistic interpretation 

 of their behaviour. Like Jennings, he denies that the 

 local action theory of tropisms can explain completely 

 the behaviour of these organisms. He would sub- 

 stitute for it another view to which his researches have 

 led him, but it is impossible, in the short space at our 

 disposal, adequately to present this view or to criticise 

 it. Undoubtedly Dr. Alverdes's work is careful, and 

 is marked throughout by independence of mind. He 

 insists, with admirable emphasis, that little progress 

 can come from the study of the Protista in unusual 

 media or in media which are artificially prepared upon 

 physico-chemical principles alone. The same argu- 

 ment might be applied with profit to all other work on 

 the Protista. 



In spite of a rather difficult and discursive style, the 

 book >ln>uld not be neglected by those who are interested 

 in the problems with which it deals. 



NO. 2763, VOL. I to] 



An Introduction to Electrodynamics : From the Stand- 

 point of the Electron Theory. By Prof. Leigh Page. 

 Pp. vi + 134. (Boston and London : Ginn and ( '■>.. 

 1922.) 10s. net. 

 Hitherto the mathematical equations of electro- 

 dvnamics have been based on the experimental con- 

 clusions of Coulomb, Ampere, and Faraday. Even 

 books which discuss relativity go no further than 

 showing that these equations are co-variant for the 

 Lorentz-Einstein transformation. In Prof. Page's 

 book, however, the equations are derived directly from 

 the principle of relativity. The mathematician will 

 appreciate this procedure as it is more logical, but we 

 think that the average reader will find the older 

 methods more convincing. The units chosen are those 

 advocated by Heaviside and Lorentz. The value of 

 the charge at any point is equal to the number of tubes 

 of force diverging from the point ; all matter is assumed 

 to be made up of positive and negative electrons ; 

 electromagnetic force is defined in terms of the electric 

 intensity of lines of force, and gravitational attraction 

 between two electrons is supposed to be negligibly 

 small. The electrons carrying a current are all of the 

 same sign, and their masses are positive. Hence 

 the " mass of the current " is greater than the sum 

 of the masses of the individual electrons compos- 

 ing it. 



The author's methods of calculating the radiation 

 from electrons are to be commended, and he also gives 

 a good account of Laue's theory of the diffraction of 

 X-rays. The formulae deduced for specific inductive 

 capacity, magnetic permeability, and metallic con- 

 ductivity agree fairly well with experimental results. 

 The theories of Faraday's experiment showing the 

 rotation of the plane of polarisation of light by a 

 magnetic field and of the Zeeman effect are given 

 briefly, but in a convincing way. We can commend 

 this book to the electrician who has an advanced 

 knowledge of mathematics and is interested in the latest 

 theories. 



Handbuch der biologischeu Arheitsiuethoden. Heraus- 



gegeben von Prof. Dr. E. Abderhalden. Lieferung 



55. Abt. V : Methoden :um Stadium der Funktionen 



der einzelnen Organe des tierischcu Organ i sinus. Teil 6, 



Heft 3. Sinnesorgane : Lichlsiini and A age. Pp. 



365-462. (Berlin und Wien : Urban und Schwarzen- 



berg, 1922.) 117 marks. 



This portion of the work, Abderhalden's " Handbuch," 



is the direct continuation of parts 3 and 41 which dealt 



with the biophysical methods used in investigating the 



living eve and its sensitivity to light. The first section, 



by Dr. Vogt of Basel, is devoted to the method of 



examining the eye with light from which the red rays 



have been absorbed by passage through a concentrated 



solution of copper sulphate and a weak solution of 



erioviridine. With such light, investigations of the 



yellow spot are rendered much easier and more accurate. 



Thesecond section of 76 pages, by 1 )r. Baslerof Tubingen. 



deals with methods which in the main are intended to 



investigate the functions of the retina and its various 



parts. Sharpness of vision, irradiation, and detection 



of movement are some of the subjects dealt with. The 



concluding section, by Dr. Struyckenof Breda, describes 



the photographic method he uses for studying the 



