NOVEMBEB 



1909] 



SCIENCE 



649 



THE MECHAXICS OF BIOLOGY 



We Americans are often pointed out by the 

 Englisli and German and French as a people 

 who do things in a hurry. Sometimes we are 

 admired for it: other times otherwise. Well, 

 we must not be too puSed up in the one case, 

 nor, in the other, feel too solitary in our guilt. 

 Two scientific books of much interest that 

 have appeared here in Paris in the current 

 fortnight are the stimulus to this sage reflec- 

 tion. 



Last year a newspaper critic began an 

 otherwise kindly review of a recent book by 

 an acid reference to college professors who 

 give a new course one year and make it into 

 a book in the next. It is true that the par- 

 ticular book under review was the outcome of 

 a college course, but President Jordan and I 

 had given that course, with annual revision, 

 for ten years, and before that it had already 

 been given for five years by Dr. Jordan alone 

 or with other colloboration. Fifteen years 

 of ripening would seem to be a decent period 

 — even for California fruit! 



The authors of the two new French books 

 I have referred to are at this very time, and for 

 the first time, giving the lecture courses on 

 which their books are based. This is at least 

 literally true of Felix Le Dantec's " La Crise 

 du Transformisme " (Alcan), and I strongly 

 suspect it to be true of Georges Bohn's " La 

 Naissance de I'Intelligence " (Flammarion). 

 Le Dantec's book is composed of the Novem- 

 ber and December lectures in his still continu- 

 ing Sorbonne course, while Bohn's course, 

 just beginning, starts off much like his book. 

 In his case, however, it may be fairer to look 

 on the book as the precursor of the course. 



In both cases the men are very competent 

 to lecture or write on their respective subjects 

 and both the books and the courses are fasci- 

 nating contributions to present-moment bio- 

 logical discussion. Each man is an active 

 exponent of a very advanced point of view in 

 his field of special interest, Le Dantec advo- 

 cating a rigorously mechanical explanation of 

 vital phenomena in general and Bohn a con- 

 sistently mechanical theory of animal be- 

 havior. 



The impulse for Le Dantec's writing and 

 the suggestion for his title lie in the swift 

 growth to almost dominating position among 

 species-forming explanations of De Vries's 

 mutation theory. He attacks this theory 

 with all the acuteness and vigor of his logic- 

 ally trained and argumentative mind. If he 

 could only bring to its aid an equal strength 

 of personal observation and experiment he 

 would be an easily triumphant antagonist. 

 But Le Dantec is more prolific of syllogisms 

 than of original observations ; is more at home 

 in his lecture room or at his writing desk than 

 in his research laboratory or in the field. And 

 his argument is too often a refinement of 

 logic or a development of terminology rather 

 than a convincing enumeration of facts that 

 carry their own irrefutable conclusion. One 

 can fight for ehemism in biology with meta- 

 physic just as as one has long fought against 

 it with the same old nicked and blunted 

 weapon. And in either case the champion 

 has a sorry tool. 



Dr. Bohn's book is of very different type. 

 It is the direct contrast in manner. It ia 

 judicial rather than lawyer-like, although the 

 author has his convictions. He suspects all 

 explanations too elaborate, but also those too 

 simple. He deplores too much theory, calling 

 for more facts. He analyzes and criticizes, 

 weighs and estimates, and then seeks the 

 simplest way out. 



Bohn finds mechanical reflexes, vital rhythms 

 and " differential sensibility " sufficient to ac- 

 count for the behavior of that great mass of 

 the animal kingdom from the Protozoa up to 

 the Crustaceans and insects. In these, with 

 their special development of sense organs, es- 

 pecially eyes, behavior begins to take on its 

 first phase of psychism — by this word being 

 meant no dualistic conception of psyche and 

 body but simply a certain degree of mentality 

 or complicated functioning of nervous system, 

 a behavior based on the association of sensa- 

 tions in addition to the tropismic responses. 

 Finally, with the advent of brained animals, 

 the vertebrates, comes the first intelligence, a 

 dominating of the sensation associations over 

 the mechanical reflexes, the tropisms. 



