NOTICES OF NEW BOOKS. 33 



These excellent " Cambridge Manuals of Science and Litera- 

 ture," in which this publication is included, bear the imprimatur 

 of the Cambridge University Press, and we are thus justified in 

 concluding that Mr. Doncaster has not misrepresented the 

 philosophical conclusions on evolutionary questions which are 

 in the main held by the zoological school of that city. Nowhere 

 is the name of Darwin more honoured, nowhere are his con- 

 clusions more deeply studied and valued, but in this manual 

 there is no assertion of that " all-sufficiency of natural selec- 

 tion " which is to many evolutionists a stumbling-block. Neither 

 is there any sign of that some time prevalent non-recognition of 

 other theories that may be said to supplement, and in some 

 points qualify, the great theory as left by its master. Thus, in 

 the discussion on "Variation," we read : — *' The recognition of 

 discontinuity in variation, which we owe chiefly to the work of 

 Bateson in England and De Vries in Holland, is one of tbe chief 

 advances which the study of the subject has made since the time 

 of Darwin." The question as to the inheritance of acquired 

 characters is cautiously discussed, and the opinion expressed 

 that most cases which at first sight seem to support the theory 

 " are equally explicable in the view that both parent and off- 

 spring are susceptible to the action of the external factor ; what 

 is inherited is not the character acquired, but the innate power 

 of acquiring it." Mendel receives a just appreciation in the 

 chapter devoted to " Mendelian Heredity," and all thinkers will 

 agree with Mr. Doncaster in the remark: " One cannot avoid 

 speculating on the possible effects on biological thought had the 

 experiments and conclusions of his now famous contemporary 

 ever come to the knowledge of Darwin." No theory in the great 

 Darwinian evangel has been more neglected and discredited 

 than that of Pangenesis ; it is now, however, apparently being 

 recognized as stimulative, *' and to a great extent it led to the 

 formulation of other theories of heredity." It will probably be 

 found to contain a still higher meaning, and we may profitably 

 find some philosophical peace from the conflicting disputations 

 of " Neo -Darwinians " and " Neo-Lamarckians" by going hack 

 to Darwin. 



Zool. 4th ser. vol. XV., January, 1911. 



