466 



SCIENCE. 



[N. S. Vol. XXIV. No. 615. 



since to the less important association of eye 

 and ear an entire chapter is given. The con- 

 sideration of migraine and hysteria leaves 

 much to be desired. The colored pictures of 

 the fundus are rather sketchy. The index is 

 not as complete as it should be to permit rapid 

 reference, nor is the paragraphing well 

 marked. The work of the publisher is excel- 

 lent as regards paper and type. The unusual 

 breadth of page gives a sense of solidity to the 

 text which is hardly restful. 



In spite of these faults and certain minor 

 errors in the spelling of proper names, the 

 book is a creditable one and with its very ex- 

 cellent companion volume will no doubt prove 

 a useful addition to medical literature. 



CoLMAN W. Cutler. 



New York City. 



SCIENTIFIC JOURNALS AND ARTICLES. 



The Journal of Comparative Neurology and 

 Psychology for September is devoted almost 

 entirely to psychological papers. Mr. Charles 

 Scott Berry first gives the results of an in- 

 vestigation of ' The Imitative Tendency of 

 White Eats,' made at the Harvard Psycholog- 

 ical Laboratory. One animal was taught vari- 

 ous tricks alone and then observations were 

 made to determine how far others would learn 

 the tricks from him by imitation. He con- 

 cludes that voluntary imitation (Morgan's 

 usage) of a certain type does exist' in white 

 rats; and though this is not of as high degree 

 as that discovered by Kinnaman in his experi- 

 ments with monkeys, it is not different in 

 kind. The next two papers are fragments 

 selected from a large mass of MSS. by the late 

 C. L. Herrick left unfinished at the time of 

 his death. In ' Applications of Dynamic 

 Theory to Physiological Problems,' Dr. Her- 

 rick applied in a concrete way to the problems 

 of heredity and vitalism the conception of 

 ' dynamic monism ' which he had begun to de- 

 velop in the philosophical journals. This is 

 followed by a brief note on ' Imitation and 

 Volition,' suggested by one of Professor Mark 

 Baldwin's discussions. In the editorial col- 

 umn, under the title, ' Objective Nomencla- 

 ture, Comparative Psychology and Animal 



Behavior,' Dr. Yerkes critically reviews the 

 work of the objective school, and the method- 

 ological problems involved are discussed from 

 a somewhat different standpoint by Dr. Baw- 

 den. Book reviews complete the number. 



The Journal of Nervous and Mental Dis- 

 ease for October opens with an article by 

 Drs. Mills and Weisenburg presenting the fol- 

 lowing propositions: (1) that the cortical rep- 

 resentation of cutaneous and muscular sensi- 

 bility is independent of motor representation, 

 that it surrounds the motor zone; and that it 

 is subdivided into a mosaic of centers, each 

 center or group of centers being anatomically 

 and functionally correlated to a motor center 

 or centers; (2) that every muscle or group of 

 muscles producing a movement or movements 

 which are represented by separate centers in 

 the cortex is topographically related to a seg- 

 ment of the skin which has also a definite 

 cortical center, this center being correlated 

 anatomically and functionally with the motor 

 center; (3) that stereognostic representation 

 like that of cutaneous and muscular sensi- 

 bility and of movements has also its inde- 

 pendent cortical area and is subdivided after 

 the manner of the motor and sensory areas. 

 This is followed by a continuation of a paper 

 by Dr. Amberg, begun in the September issue, 

 giving the histories of a number of cases of 

 ear affections and mental disturbances. 



DISCUSSION AND CORRESPONDENCE. 



ON THE DOPPLER EFFECT. 



In a recent number of Science (Vol. 

 XXIV., p. 250) there appeared an article by 

 Dr. Paul R. Heyl suggesting a plan for in- 

 creasing the Doppler effect by observing a 

 rapidly moving image instead of a moving 

 source, the motion being magnified by placing 

 the source just outside of the focus of a con- 

 verging mirror. If, however, we consider 

 that the wave-length of the separate rays (or,, 

 if preferred, of the elementary pencils) is 

 independent of their point of intersection — in 

 other words, of the position of the image — it 

 appears that the only modification of wave- 

 length observed in an instrument at rest rela- 

 tively to the mirror will be due to the motion. 



