422 



SCIENCE 



[N. S. Vol. XXVII. No. 



•own view of the origin of species is, we 

 .gather, a peculiarly composite one; in many 

 regards it resembles Plate's, and is a com- 

 pound of Darwinism, orthogenesis, mutation 

 (mildly emphasized), Lamarckian use-inherit- 

 ance, and the "unknown factors." It is 

 clear that he attaches less importance than 

 Plate to the Darwinian factor. Thus he be- 

 lieves that Plate's " passive adaptations " may 

 be explained by other means than by natural 

 selection, and in this regard he derives help 

 from the views of Roux to explain mech- 

 anically the initiation of delicate inner 

 adaptations. So, also, it appears, he looks 

 upon organic selection as not strictly neo- 

 Darwinian, for, he argues, if ontogeny can 

 constantly bring into the organism a bene- 

 ficial structure (as in orthogenesis), what 

 need is there for the selection of minute 

 Tjeneficial variations? On the other hand, 

 he does not sympathize in any sense of the 

 word with teleologicians : and in this regard 

 Tae stands sharply cut off from several recent 

 writers, for we can not deny that these reac- 

 .tionaries are gathering strength. In explain- 

 ing " purposive " adaptations he sides rather 

 with Plate, but attributes little value to 

 amphimixis, and he has little leaning to 

 germinal selection. To the various micro- 

 meric theories, as well, his attitude is non- 

 sympathetic. To the influence of isolation 

 he gives considerable space and takes a middle 

 ground in estimating its importance. With 

 many critics of selection he agrees that too 

 much prominence in the problem of the 

 origin of species has been given to artificial 

 selection. At the same time he is a convert 

 to the causo-meehanical conception of ortho- 

 genesis, which he calls " one of the most 

 important matters connected with the whole 

 great problem of descent," one which deals 

 with the " basic problem," for it touches " the 

 problem of beginnings." He does not indi- 

 cate, however, to what degree this form of 

 evolution can be regulated, and in this re- 

 gard is unlike Weismann, who seeks to con- 

 struct a mechanism, which corrects auto- 

 matically too extreme a type of orthogenesis. 

 Kellogg's own conception of evolutionary 

 •processes, then, is extremely complicated: and 



we have not yet included in it the " unknown 

 factors." This article in his faith he declares 

 more emphatically, I think, as he progresses 

 in the book. But it is clear that he does not 

 consider these unknown factors as in any 

 sense vitalistic: he thinks unnecessary a 

 " mysterious tendency of the germ plasm to 

 vary," and, nearing an ultimate problem, 

 suggests that the " inevitable non-identity of 

 vital process and environmental conditions 

 may alone be enough to supply the automatic 

 modifying principle, antedating and preceding 

 selection, which must affect change determi- 

 nate, though not purposeful. Naegeli's auto- 

 matic perfecting principle is an impossibility 

 to the thorough-going evolutionist seeking for 

 a causo-mechanical explanation of change, 

 but an automatic modifying principle which 

 results in determinative or purposive change 

 ... is not that the very thing provided by 

 the simple physical or mechanical impos- 

 sibility of perfect identity between process 

 and environment in the case of one individual 

 and process in environment in the case of 

 any other ? " But this conception of Kellogg 

 is, so far as we can see, little more than the 

 restatement of the idea of environment and 

 variability which has been woven into the • 

 warp of discussion ever since evolution has 

 been seriously considered. 



In a work of this kind, one should be grate- 

 ful for its utility and its general accuracy, 

 and not go far out of the way to dig into its 

 structural details. Without wishing to be 

 unduly critical, one might nevertheless point 

 out that in this Darwinism to-day there is 

 no reference to many and notable discussions 

 of the last half dozen years, some of which, by 

 the way, were published in the pages of this 

 journal. Nor is the neo-vitalistic side of evolu- 

 tional philosophy given due consideration — not, 

 be it understood, that the reviewer is in keen 

 sympathy with this point of view. Nor is 

 the more wholesome neo-Lamarckian philos- 

 ophy expounded adequately. In such a work, 

 there should have been some reference to 

 Pauly's " Darwinismus and Lamarckismus " 

 (1905), and some citation to the Lamarckian 

 utterances of so distinguished a biologist as 

 Professor Boveri (in his address (1906) as 



