August 10, 1906.] 



SCIENCE. 



175 



he says (p. 149) : " It follows, accordingly, 

 that in neither of the known kinds of bastard- 

 ization, the Mendelian or the unisexual, is 

 there any evidence that variations or muta- 

 tions are produced by these processes. 

 Parental qualities are transmitted according 

 to more or less definite laws, but no new ones 

 are produced." On the basis of such consid- 

 erations he concludes that acquired characters 

 are inherited. "Indeed the very postulation 

 of the question, * are acquired characters in- 

 herited ? ' is absurd. It should read rather, 

 ' what kinds of acquired characters become in- 

 herited ? ' " Eegarding the statement of de 

 Vries that the answer to this question ' de- 

 pends to a great extent upon a word play ; just 

 according as one chooses his definition for 

 acquired characters, he regards them as herit- 

 able or not,' Montgomery says : 



Here, however, de Vries himself makes a word 

 play; acquired characters, according to him, are 

 those only which do not arise suddenly, i. e., indi- 

 vidual variations and not mutations. But ac- 

 cording to all essential ideas of his mutation 

 theory the mutations are much more distinctly, 

 even solely, steps in the formation of races, and 

 a step in racial progress is surely nothing less 

 than an acquisition. 



This is as striking an illustration as could 

 be found of the need of clear definitions, and 

 of the fact that long continued discussions in 

 science more frequently arise from misunder- 

 standings than from fundamental differences 

 of opinion. For what Montgomery calls ' ac- 

 quired characters ' or ' steps in racial progress,' 

 would be called by Weismann or de Vries 

 ' germinal characters,' while the question of 

 the transmissibility of ' acquired characters ' 

 in the sense of Weismann, i. e., somatic char- 

 acters which are, ex hypoihesi, not represented 

 in the germ, is not discussed by Montgomery. 

 Weismann and raany others use the term ' ac- 

 quired character ' in a peculiar and specific 

 sense, Montgomery with a general and col- 

 loquial meaning. 



The sixth chapter deals with the ' Trans- 

 mutation of Species.' It begins with an ap- 

 preciative account of the part of Lamarck in 

 establishing the theory of evolution, and an 

 interesting discussion of the question of the 



inonophyletic or polyphyletic origin of organ- 

 isms. The unfortunate prominence of hypo- 

 thetical ancestors in many evolutionary dis- 

 cussions is excellently set forth in these words : 

 " From the casual inspection of certain wri- 

 tings, and most unfortunately those intended 

 for beginners, one might infer that the 

 Moneron, the Gastroea, the Trochozoon, and 

 the Bathy'hius were more important, if not 

 more real, than the living animals around us." 



He concludes that transmutations are 

 definitely directed and that they may be dis- 

 continuous, by means of mutations, as de Yries 

 has shown, or continuous, by means of varia- 

 tions. As an illustration of the latter he 

 considers the different geographical races or 

 subspecies of the song sparrow, Melospiza 

 cinerea, the geographical as well as morpho- 

 logical intergradations of which indicate that 

 these are not mutants but variants. He con- 

 cludes, therefore, that 'the mutation theory 

 has not disproved the possibility of perfectly 

 gradual transmutation of species, but has only 

 shown that sometimes transmutation may not 

 be a gradual process.' The author takes an 

 equally broad view with regard to the causes 

 of mutation and variation, holding that 'the 

 factors are neither purely extrinsic, nor purely 

 intrinsic, but a combination of the two^' 



The chapter on the 'Parallelism of the" 

 Ontogeny and the Phylogeny' contains an ex- 

 tremely interesting and valuable resume of the 

 ■ recapitulation theory.' This is followed by 

 a critical consideration of the whole question, 

 and the conclusion is reached " that the 

 embryology does not furnish any recapitula- 

 tion of the phylogeny, not even a recapitula- 

 tion marred at occasional points by secondary 

 change. * * * An analysis of the stages 

 during the life of one individual can in no 

 way present a knowledge of its ancestry; and 

 the method of comparing non-correspondent 

 stages of two species is entirely wrong in prin- 

 ciple." 



In the chapter on ' Morphological Com- 

 parisons ' the author argues that in compari- 

 son of organisms the whole life cycle should 

 be considered as well as all structural char- 

 acters, and he strongly insists that only corre- 

 sponding stages in the ontogeny can properly 



