524 'Journal of Comparative Neurology and Psychology. 



lariae remind one very strongly of the behavior of individuals in a colony, such as of 

 bees or ants, all of which work together to accomplish a definite end. When a 

 starfish is placed in a new situation, where there is a problem to solve, the move- 

 ments are at first varied, but soon a definite impulse to act in a certain way appears 

 to be formed, after which all the parts work together with a unity to bring about 

 the results on this line. Jennings calls this the unified impulse. When this is 

 once established the movements tend to continue along this course, even if the con- 

 ditions be changed and new stimuli introduced. This latter tendency the author 

 believes is " evidently akin to the formation of a habit. " Moreover, he has actually 

 been able to demonstrate habit formation in the starfish by training individuals 

 to use different rays in righting themselves from those which they naturally employ. 

 The effect of this laborious training, however, soon disappears. 



Considerable space is devoted to a discussion of these results in relation to 

 Driesch's postulation of a "Psychoid" or "Entelechy," a sort of vitalistic prin- 

 ciple, which that author believes the only way of explaining these adaptive reactions. 

 While Jennings does not claim to have analyzed all the factors which enter in, he 

 nevertheless maintains — and very properly, it seems to the reviewer — that Driesch's 

 would-be explanation is "merely a way of collecting all the difficulties together and 

 giving the bundle a name." "The Entelechy would be a problem not a solution," 

 while "to accept the Entelechy unanalyzed and unexplained is merely to give up the 

 problem as insoluble. " The author's alternative answer to the question is pregnant 

 with suggestion and may well be quoted : 



"The only other answer that can be given is that the precise way each part shall 

 act under the influence of the stimulus must be determined by the past history of 

 that part; by the stimuli that have acted upon it, by the reactions which it has given, 

 by the results which these reactions have produced (as well as by the present rela- 

 tions of this part to other parts, and by the immediate effects of its present action). 

 In other words, this complex harmonious working of the parts together is only intel- 

 ligible on the view that there is a history behind it; that it is a result of development. 

 We can not look upon it as a final thing (*etwas Letztes, Naturgegebenes'), because 

 there is a history behind it, and we know as solidly as we know anything in physiol- 

 ogy that the history of an organ does modify it and its actions — in ways not yet 

 thoroughly understood, doubtless, yet none the less real. The starfish that we have 

 before us has an actual history of untold ages, in which it has existed as germ plasm 

 or otherwise, and there can be no greater mistake in physiology than to leave this 

 out of account. The modifications induced in organisms by their experiences, 

 either while existing as germ plasms or as individuals, are as clearly a part of physi- 

 ology as is the study of digestion, and their existence is not less doubtful." 



LEON J. COLE. 



Buttel-Reepen, H. v. Are Bees Reflex Machines.^ An experimental contribution to the natural 

 history of the honey-bee. Translated from the German by Mary H. Geisler. Pp. 48, $0.50. 

 The A. I. Root Company, Medina, Ohio. 1907. 



Students of animal behavior and comparative psychology will welcome this 

 translation of voN Buttel-Reepen's noteworthy discussion of the behavior and 

 psychology of the bee. The monograph may now be used to advantage in connec- 

 tion with introductory courses in Animal Psychology. Apparently the translator 



