172 



SCIENCE 



[N. S. Vol. XLIX. No. 1259 



ularly in the discussion of pliototropism, for 

 whieli the experimental evidence is the most 

 comprehensive. 



Doubtless the portion of the book liable to 

 excite the most general interest is liat dealing 

 with " Instincts " and " Memory images and 

 tropisms." The author's views on these topics, 

 now well known, are here incisively restated, 

 and on some points extended. It is held that 

 the preservative instincts are tropisms; and 

 that the " problem of free will " is essentially 

 solved through recognition of the orienting in- 

 fluence of memory images — ^which, being in 

 man multitudinous, render impossible the pre- 

 diction of individual behavior. The orienting 

 powers of memory images afford an inviting- 

 topic for research, and one as yet very inade- 

 quaitely explored. 



Two directions in which the results of trop- 

 istic analysis are of use to the naturalist are 

 not so fully developed as one might wish: the 

 value of determinate behavior in animals as a 

 starting point for the experimental invesitiga- 

 tion of irritability, and the significance of the 

 physical viewpoint for the analysis of organic 

 phenomena as actually seen in nature. The 

 limitations of space, however, have compelled 

 great brevity of -treatment. ISTevertheless, the 

 reader of this book should succeed in gaining 

 fast hold of the conception that mere complex- 

 ity is no bar to ultunate clarity of understand- 

 ing in these matters ; and should, in addition, 

 acquire a healthy distrust toward the indis- 

 criminate application of "laboratory results" 

 to field conditions. The tropism doctrine, in 

 other words, is in no sense an artificial simpli- 

 fication of " animal behavior." In this connec- 

 tion, specifically, the book will be particularly 

 valuable as an introductory manual for stu- 

 dents. To the investigator, already familiar 

 with these ideas (it is to be presumed, but 

 not in all instances correctly), the book has 

 less new material to offer. 



A bibliography of some 554 entries, not very 

 well arranged and comprising some repetitions, 

 together with a brief index of two and a quar- 

 ter pages, complete the book. It is stated, 

 rather bluiitly, that the bibliography inten- 

 tionally excludes " controversial and amateur- 



ish publications," and to that extent it should 

 prove a useful guide. The citations are less 

 complete for the years since 1911 than for the 

 preceding period. No attempt has been made 

 to critically discuss the contents of the publi- 

 cations listed, which is in many respects a 

 blessing; for it is as a unitary presentation of 

 the author's views that the monograph will be 

 read vpith interest by all workers in this field. 

 W. J. Crozier 

 University of Illinois, 

 Chicago 



THE GEOLOGICAL SOCIETY OF 

 AMERICA 



The thirty-first annual meeting of the Geological 

 Society of America was held in the rooms of the 

 Department of G-eology, Johns Hopkins Univer- 

 sity, Baltimore, Md., on Priday and Saturday, De- 

 cember 27-28, 1918, under the presidency of Dr. 

 Whitman Cross of the United States Greological 

 Survey. 



The following program was presented: 



Geology as a basis of citizenship: Joseph Pogue. 

 (Read by title.) 



Sources of and tendencies in American geology: 

 Joseph Barrell. 



Geology as a synthetic science: Waeeen D. Smith. 

 (Read by title.) 



The United States Geological Survey as a civic in- 

 stitution during the war: Sidney Paige. 



The military contribution of civilian engineers: 

 George Otis Smith. 



Presentation of geological information for engi- 

 neering purposes: T. "Wayland Vaughan. 



Engineering geology in and after the war: 

 Charles P. Berkey. 



Geology in the Students Army Training Corps: 

 Herbert E. Gregory. 



Cooperation in geological instruction: Herbert E. 

 Gregory. 



Map making, map reading and physiography in the 

 training of men for the army and navy: Wal- 

 lace W. Atwood. 



War work by the department of geology at the 

 University of Oregon: Warren D. Smith. 

 (Head by title.) 



Recent earthquakes of Porto Sico: Harry F. Keid 

 and Stephen W. Taber. 



Structure of the Pacific ranges of California: 

 Bailey Willis. 



Migration of geo-synclines : Amadeus W. Geabad. 



