Januaey 3, 1896.] 



SGIENGE. 



27 



special case. His standpoint is indicated in liis 

 preface, in which he says: 



"My butterflies demonstrate, as said above, the 

 impotence of natural selection over a -wide territory ; 

 their formation of species occurs evidently without 

 any influence o£ Darwinian selection, and, therefore, 

 disproves Darwinism completely. * * * * There is 

 no origin of species iy natural selection, but only a 

 preservation of species already existing. Tlie assump- 

 tion that natural selection can bring forth new species 

 rests upon a gi-oss defect of reasoning (Deukfehler). 

 Natural selection cannot cause new species to arise, 

 either by the formation of new characteristics or by 

 the division of existing chains of organisms into 

 species. My butterflies show, in complete contradic- 

 tion to the Darwinian doctrine, that new characters 

 arise by development in a few predetermined direc- 

 tions ( Orthoffenesis) or by organic growth ( Organophy- 

 sis) from physiological causes. They show that it is 

 essentially a still stand {Genepistase) at determinate 

 stages of development, which separates a chain of 

 organisms into species, together with certain other 

 causes, such as the preventing of impregnation {Kyes- 

 amechanie) and development by jumps {Halamato- 

 geiiesis)." * 



He also claims that he presents only facts — 

 no suppositions or hypotheses: 



If Prof. Elmer's claims are correct, his re- 

 searches mark one of the great epochs of 

 biological discovery. It is, therefore, desirable 

 to determine with precision the nature and 

 value of the evidence which he presents. 



The study of his work on butterflies (includ- 

 ing both the present second part and also the 

 first, published in 1889) shows that the facts of 

 actual observation are solely the markings and 

 geographical distribution of species of the genus 

 Papilio aiictorum. From these observations our 

 author has deduced a systematic arrangement 

 of several groups of species, so as to present 

 them in what he believes to be their true phylo- 

 genetic relationships. From the standpoint of 

 the systematic entomologist Elmer's work is 

 certainly both interesting and valuable, since 

 the figures and descriptions are very painstak- 

 ing, and his groups are natural ones, and we 

 may even go further and admit that his group- 

 ing of the species is in the main correct. Here- 

 with we come, not without some surprise after 

 the assurances of the preface, to the end of 



* Slightly abbreviated. The italics are the author's. 



Elmer's positive facts. The remainder of his 

 book is constructed of interpretations of the 

 facts, and these interpretations cannot be desig- 

 nated otherwise than as a series of unproven 

 assumptions and hypotheses. We may indicate 

 the reasons for this characterization by a few 

 illustrations of his reasoning. Thus he states 

 (pt. i, p. 2) that in all animals longitudinal 

 stripes are primary markings, longitudinal rows 

 of spots secondary, and transverse markings 

 tertiary. By this rule he is able to decide 

 easily which living species of Papilio are nearest 

 the ancestral forms. Surely such a universal 

 i-ule needs to be demonstrated, not proclaimed 

 ex-cathedra. His laws of the genesis of species 

 are deduced thus: In a series of species of 

 Papilio there may be ancestral forms with much 

 black and descendent forms with little (Anti- 

 phates group), or just the other way the de- 

 scendants blacker than the ancestors (Leos- 

 thenes-Ajas group) yet all the species concerned 

 are living and no proof is oifered that this or 

 that form is ancestral, we are simply told that 

 it is so. Again he finds a series of species, 

 which diiier from one another by the width of 

 certain dark bands, each species taking its 

 place according to the width of the bands. 

 Such a series is his proof of halmatogenesis, and 

 he entirely passes by the possibility that there 

 may have been intermediate forms with the 

 simple denial of their existence. Now it is cer- 

 tainly possible that the species ol Papilio arise 

 by discontinuous variation, to use Bateson's 

 felicitious term, but between what seems possi- 

 ble in the present state of our knowledge, and 

 absolute certainty there is a vast abyss, across 

 which Prof. Eimer airily makes his way with 

 the bare affirmation ' my butterflies prove hal- 

 matogenesis.' Not a word throws any light on 

 the question how do they prove it ? 



Prof. Eimer lays stress upon the direction of 

 the assumed development of a series of forms, 

 and from the fact that a series of species may 

 exhibit progressive increase in a certain char- 

 acter, he infers that the progress is a prede- 

 termined development. He overlooks this 

 simple consideration that no matter how evolution 

 is caused it must be in some direction, and the 

 mere observation of that direction cannot prove that 

 there was a predetermining tendency to the ances- 



