124 



SCIENCE. 



[N. S. Vol. II. No. 31. 



ginning and during the continuance of the 

 current from G being established, and as 

 the whole action is comprehended in these 

 two periods of time, this apparently inex- 

 plicable fact would seem to be explained. 



TEE PRESENT PROBLEMS OF ORGANIC EVO- 

 LUTION* 



At the outset of a conference on the sub- 

 ject of evolution, it is necessary that we 

 understand what we mean by the term. 

 Evolution is ci-eation by energy which is in- 

 trinsic in matter, and is not creation by 

 energy exclusive^ without the evolving 

 matter. Those who explain creation by in- 

 terference from an external creative power 

 are not therefore evolutionists. This view 

 of creation is opposed to the natural ten- 

 dency to account for phenomena not other- 

 wise explainable, by an appeal to a super- 

 natural cause. If we desire to know the 

 truth, however, in this or any other matter, 

 it is necessary to divest ourselves of prepos- 

 sessions and preferences, and relj^ exclu- 

 sively on the evidence. But the result of 

 this method in the case of organic evolution 

 is to demonstrate, in my opinion, that the 

 elements of mind have had an important 

 place in the process and have materially 

 influenced the results. 



The evidence for organic evolution, it is 

 well known, is derived from three sources: 

 First, the spontaneous variations from uni- 

 formity of structure, frequently observed iu 

 plants and animals ; second, the regular 

 succession of forms displayed in the historj' 

 of life, taught by the science of paleontology ; 

 third, the recapitulation of the same succes- 

 sion, more or less completely, in the embrj'- 

 onic histories of organic beings. As time 

 passes on, the evidence of the origin of species 

 and the groups into which they fall by 



* Abstract of a lecture by Professor E. D. Cojie 

 given at the opening of the Conference of EeoluUonists 

 at Greenacre-on-the-Piscataqua on July 6th and re- 

 ported in the BoMon Transcript. 



modification during descent from preexistent 

 forms becomes more and more perfect. 



The problems presented by the preceding 

 facts for solution may be embraced under 

 two heads: (1) how are the A'ariations or 

 changes in individuals produced ? and (2) 

 when produced, are they inherited and so 

 accumulated, or not ? 



The question as to the cause of variation 

 is difiBcult of solution. The attempt to solve 

 it must be preceded bj' a knowledge of what 

 the lines of variation which constitute evo- 

 lution have been. These are presented by 

 the study of the life of past geologic ages. 

 From this source we learn that there has 

 been a successive improvement in the me- 

 chanisms of organic beings. Since the me- 

 chanisms are constructed of always plastic, 

 and for a time growing, material, it looks 

 probable that thej' have been produced by 

 the movements of the organism itself. This 

 suspicion is made a certainty when we learn 

 that new mechanisms are readily constructed 

 by oi'ganic beings, to take the place of their 

 normal ones which have been injured or 

 lost. The annals of surgerj^ and of ortho- 

 pedic hospitals are full of such cases, and 

 the lower animals are still more capable of 

 producing new structures to take the place 

 of old ones than is man. I do not mean by 

 this the reproduction of lost parts, as in the 

 case of the crab and its pincer; but I mean 

 the construction of a new joint or segment 

 in a new place, which is obviouslj' moulded 

 by the mechanical action of the parts. 



The movements of animals have led their 

 progressive evolution, and a great many 

 structures have been modified in conse- 

 quence in ways which are indirect, and 

 whose characters do not always betray 

 their real efficient cause without full inves- 

 tigation. Per contra, the absence of motion 

 has resulted in degeneracy and retrogres- 

 sive evolution. This is amply demon- 

 strated bj' the results of parasitism. Para- 

 sites are always degenerate. This is the 



I 



