Apbil 3, 1908] 



SCIENCE 



535 



experimental or traumatic stimulation, or by 

 repeated cases of identically similar lesions, 

 are definitely indicated to be concerned witb 

 the given functions. The general motor and 

 sensory (somsestlietic) areas are known witb 

 practical certainty, and experiments have 

 enabled us to subdivide them for different 

 parts of the body ; and the areas concerned 

 more than any others with the four special 

 sense organs are generally accepted, though 

 not given definite boundaries. But to go 

 much further, our knowledge will have to ad- 

 vance past the stage, not yet reached, when 

 cerebral tumors may be positively diagnosed 

 both as to existence and especially as to exact 

 position, and when positive interpretations 

 may be made of the varied symptoms accom- 

 panying many of the smaller brain lesions. 



Further, purely histological studies of cere- 

 bral localization are practically worthless as 

 to the existence of " centers." The function 

 of an organ or part of an organ must be 

 previously known, for function can not be 

 inferred from anatomy. With microscopic 

 anatomy especially, one would be more help- 

 less than, for example, he would be with a 

 steam engine or its parts, unknown and seen 

 for the first time. Just as the leaves of a 

 tree are not exactly alike, so are no two gyri, 

 of the same or of diilerent cerebra, exactly 

 alike as to contour, depth of sulci or thick- 

 ness of pallium. These superficial differences 

 are as marked as internal or structural differ- 

 ences. If analyzed far enough, no two sec- 

 tions of a gyrus will be found identical and, 

 by carefully comparing sections of adjacent 

 gyri, differences of structure are easily distin- 

 guishable. All gyri peculiarly situated, and 

 therefore peculiarly shaped, show peculiar 

 structural differences. If a well-defined dif- 

 ference of function of a whole or a part of 

 an organ is positively known, functional 

 significance may then be assumed and at- 

 tributed to the structural differences, and such 

 assumptions may or may not be correct as the 

 history of the study of many organs shows. 

 Many of the differences in number, size and 

 lamination of the cell bodies, and therefore of 

 the axones, of the various gyri may be more 

 truly explained as due to different intra- 



cranial physical conditions present during the 

 processes of grovrth. The existence of the 

 gyri and their superficial differences are ex- 

 plained in this way. 



The execution of the book is fine. The 

 paper is good, the print neat and clear, axid 

 the reproduction of the illustrations is excel- 

 lent. 



The intent of a book of this kind is to aid 

 the student in making a more detailed study 

 of the nervous system than is expected with 

 the ordinary text-books of anatomy. Dr. 

 Santee will agree that in making such ad- 

 vanced studies, the student should be urged 

 in every possible way to consult frequently 

 the literature of the subject, yet, no bibliog- 

 raphy is given nor is there given an index 

 of authors consulted during the preparation 

 of the book. 



Irving Hardesty 



Berkeley, Califoknia 



Introduction to Higher Algehra. By Maxime 

 BocHER, Professor of Mathematics in Har- 

 vard University. Prepared for publication 

 with the cooperation of Mr. E. P. E. 

 Duval, Instructor in Mathematics in the 

 University of Wisconsin. New York, The 

 Macmillan Company. 1907. Pp. xi + 321. 

 Analytic geometry is one of the most useful 

 solvents of algebraic difficulties. Among 

 other important solvents of compounds of 

 higher algebra are the group theory, the dif- 

 ferential calculus, and the theory of immbers. 

 In the present work analytic geometry is so 

 frequently employed that a good elementary 

 knowledge of this subject is an indispensable 

 prerequisite. Group theory is used very much 

 less frequently and the necessary concepts of 

 this subject are developed very briefly but 

 clearly. The Galois theory of algebraic equa- 

 tions and the explicit theory of congruences 

 are entirely omitted and invariants are treated 

 very briefly. The omission of such important 

 matters seems justified by the title, as it is 

 not intended to be a compendium, but really 

 an introduction to higher algebra. 



The reader should, however, not get the im- 

 pression that he is dealing with a work which 

 is like other so-called higher algebras pub- 



