THE METHOD OF ORGANIC EVOLUTION. 419 



that they constitute a discontinuous series, and lie asks "Is it not 

 then possible that the discontinuity of species may be a consequence 

 and expression of the discontinuity of variation T' He then states 

 that on the received hypothesis, "Variation is continuous, and the dis- 

 continuity of species results from the operation of selection." This, 

 liowever, is not quite a correct statement of the received hypothesis if 

 "discontinuous" is used in Mr. Bateson's sense, as including every 

 change of color which is not by minute gradation, and every change in 

 number of repetitive parts — as of vertebric, or of the joints of an antenna, 

 or the rings of a worm — which is not by a gradation of the part from 

 a minute rudiment. Such changes of color or in the number of parts 

 are admitted by all Darwinians as, in many cases, constituting a part 

 of that individual variation on which modification of species depends. 

 It is, however, on the sui)posed rejection of this class of variations by 

 Darwinians that he bases what he terms "an almost fatal objection" 

 to their theory. 



lieturning, however, to the supposed overwhelming imi)ortance of 

 discontinuous variation, we pass on to the last chapter of the book, 

 headed " (Jonclnding reflections," and we read : "The first object of this 

 work is not to set forth in the present a doctrine, or to advertise a solu- 

 tion of the problem of species," and then follows immediately a further 

 discussion of this very theory of discontinuity, which is set forth as a 

 doctrine, and as a help to the solution of that problem. We are told 

 that the difficulties of the accepted view "have oppressed all who have 

 thought upon these matters for themselves, and they have caused some 

 anxiety even to the faithful;" it is urged that "the discontinuity of 

 which species is an expression has its origin not in the environment, 

 nor in any phenomenon of adaptation, but in the intrinsic nature of 

 organisms themselves, manifested in the original discontinuity of varia- 

 tion ;" that, "the existence of sudden and discontinuous variation, that 

 is to say, of new forms having from their first beginning more or less 

 of the kind of perfection that we associate with normality, is a fact that 

 disposes, once and for all, of the attempt to interpret all perfection and 

 deflniteness of form as the work of selection." And then comes the 

 positive statement "theexistenceof discontinuity in variation is there- 

 fore a final proof that the accepted hyi)othesis is inadequate" (j). 568), 

 and after several more pages of illustration and argument, the final 

 conclusion is reached that "it is quite certain that the distinctness and 

 discontinuity of many characters is in some unknown way a part of 

 their nature, and is not directly dependent upon natural selection at all." 



Before going further it will be well to make a few observations on 

 these very definite and positive conclusions at which Mr. Bateson has 

 arrived ; and it must be remembered that this volume deals only with 

 one portion of the subject even of discontinuous variation, which is 

 itself, if we exclude monstrosities, only a small fragment of the whole 

 subject of variation. The impression that will be produced on those 



