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POPULAR SCIENCE MONTHLY 



In short, therefore, it is clear that if meaningless resemblances are 

 numerous and striking, one can accept protective resemblance and 

 mimicry only in instances which have been fully demonstrated. And 

 we may in the meanwhile mark as doubtful numerous cases which now 

 pass current in zoological literature. Among these would, I believe, 

 fall the famous leaf-like butterfly, Kallima, which Weismann has 

 adopted as the ne plus ultra of protective resemblance, for in the lack 

 of adequate experimental evidence even this form may prove to be a 

 meaningless resemblance, and not the product of selection. That it 

 may be, and probably is, of protective value at the present time can 

 as readily follow from an accidental resemblance which happens to 

 turn out to be valuable as from one which has been the product of 



Fig. 9. Tree-hoppers whose appearance suggests birds. After Gibson in Century. 



(Cut kindly loaned by Dr. Skinner.) 



numberless selected variations. In fact, it is quite credible, it seems 

 to me, that accidental favorable variation may have furnished the basis 

 of many a useful resemblance — as some mutationists believe. And 

 there are no peculiar "adaptive characters" in Kallima which can 

 safely be construed as more complicated than the meaningless char- 

 acters of the Taira crab. For in what way is the resemblance of a 



