( 447 ) 



that work were of little consequence for the systematist. Eimer replies ( Orthogenesis 

 p. 47), that he is content with the fact that other workers have repeatedly 

 expressed their open acknowledgment of his researches having opened quite new 

 ways for classification. I am aware that in descriptive entomology the methods 

 of comparative morphology are not generally employed, and it would certainly 

 be a great success, if through Artbildting these methods became better known to a 

 good many classifiers of Lepidoptera. It was not this I had in view when I wrote 

 the above sentence. I meant, on the contrary, to state that the classificatory results 

 in Arthildung I., i.e. the grouping, the kind of relationshij) which Eimer believed 

 himself to have demonstrated as being correct, were of no consequence, simply 

 because these results were to a large extent quite wrong. That other workers 

 agree with Eimer, that may be ; but I very much doubt that a single one of them 

 has examined the facts upon which the conclusions are based. One may agree 

 with Eimer in the belief that acquired characters are hereditary, and that Natural 

 Selection is not the factor in Evolution, but disagree nevertheless with him in 

 respect to the facts brought forward to " prove " those contentious. These 

 general contentions are surely not new, their repetition will not help us, and the 

 "proof" of their correctness is certainly not given by advancing observations 

 which on closer examination are either fallacious or inconclusive. In Orthogenesis 

 only one entomologist is mentioned as a supporter of Elmer's opinions. Dr. K. 

 Eschcrich, the results of whose studies on the wing-pattern of a genus of Coleoptera, 

 Fonahris, are quoted in Arthihlimg, I.e., p. 7. According to Escherich — I expressly 

 state that I am not going to criticise that author, I merely mention his results here 

 because they are said by Eimer to agree with his — there are four main types of 

 wing-pattern in Fonabris, the wings being (1) longitudinally striped, or (2) 

 spotted, or (3) transversely banded, or (4) unicolorous; the i)hyletically oldest 

 pattern is the longitudinal stripes, which developed consecutively into spots, 

 these into transverse bands, and resulted finally in monochromatism. [I mention 

 I'or the sake of explanation that Escherich has adapted the wing-pattern of Fonabris 

 to the scheme of development given by Eimer. Those four phases in the mutation 

 of the wing-pattern form_ the starting-point of his research.] Escherich's 

 longitudinal stripes are in the direction of the veins, and his transverse bands 

 at right angles to them; Elmer's longitudinal bands are, on the contrary, at right 

 angles to the veins (like Escherich's transverse bands), and his transverse bands 

 correspond, morjAologically, to Escherich's longitudinal ones. The result of 

 Elmer's researches in Lepidoptera is that the bauds across the veins are the 

 phyletically older, while Escherich maintains for Coleoptera that the bands in 

 the direction of the veins represent the ancestral pattern. Are the two results 

 really in accordance with one another, as is maintained in Orthogenesis p. 7 ? 

 The same kind of arguments which led Escherich to conclude that the steps in the 

 develojjment of the pattern were (1) bands with the veins, (2) spots, and (3) bands 

 across the veins, induced Eimer to infer that the development had taken place in 

 exactly the opposite direction. 



What I have said will suffice, I hojie, to enable the reader to come to an 

 opinion about the correctness of the classification in Artbildung, and to judge for 

 himself whether there was justification (1) for the assertion in Artbildung I. that 

 the wing-pattern is the very best guide in tracing out the relationship of species 

 of Lepidoptera, and (2) for my contention that the classificatory results were to 

 a great extent wrong. 



