304 THE EVOLUTION OF SEX. 



laws of organic growth. An active school of neo-Lamarckians, 

 such as Cope and Packard, has arisen in America ; while 

 Spencer has re-emphasised the importance both of function and 

 of environment as factors in organic evolution, supported more- 

 ever in this position by the experimental work of Semper and 

 others. The last published essays of Spencer may be referred 

 to in illustration of the unended state of the controversy, but 

 at the same time of the growing tendency to limit the importance 

 of natural selection, and as a good instance of successful 

 endeavour to recognise the measure of truth in the different 

 theories. Wallace remains staunchest among the upholders of 

 the theory of natural selection, for his share in which he seems 

 ever to refuse to take to himself sufficient credit ; but it is 

 interesting to notice, that in his recent valuable work, in re-in- 

 forcing his old objections against the importance which Darwin 

 attached to sexual selection, he has made admissions welcome 

 to those of us who believe that the shoulders of natural selection 

 have also been overburdened. As we have already noticed, 

 the phenomena of male ornament are discussed and summed 

 up as being " due to the general laws of growth and develop- 

 ment," and as such that it is " unnecessary to call to our aid so 

 hypothetical a cause as the cumulative action of female pre- 

 ference." Again " if ornament is the natural product and direct 

 outcome of superabundant health and vigour," — a view to which 

 the reader of the preceding pages can be no stranger, — " then 

 no other mode of selection is needed to account for the presence 

 of such ornament." Granted, but does not the author see, that 

 if the origin of characters so important as those often possessed 

 by males is to be ascribed to internal constitution rather than 

 to external selection, the origin of this, that, and the other set 

 of characters will next be explained in the same way, as the 

 heretics are in fact now doing. In pulling down the theory of 

 sexual selection in favour of that of natural selection, Mr 

 Wallace has really handed over Mr Darwin's elaborate outwork 

 to the enemy, who will not fail to see its value for a new assault. 

 Before we conclude this necessary historical sketch, we 

 must however refer to the subject of debate recently re-opened 

 by Weismann, to whom, as one of the foremost of European 

 naturalists, the reader's attention has already been so frequently 

 directed. To a very large extent at least, we and our fathers 

 have believed that characters acquired by the individual 

 organism from functional or environmental conditions might be 



