XXVII 



what must be considered relics amongst the colour spots in Rhopalocera proves 

 the existence of the evolutionary change of these in the clearest manner. Such 

 a study, however, only becomes possible of course when one has learned te 

 interpret these changes, not as the result of accidental climatic conditions or 

 similar airy assumptions — the ignorant would call it the action of spirits — 

 but as that of regular manifestations of natural evolution. In which connection 

 one may with advantage ponder over the words of Prof. Dr. Klaaisch when 

 proceeding to the ontoological comparison of the Neanderthal Gorilla type 

 with the Aurignac Orang type, {Die Umsc/iau, Sep/, j, igio), he states that 

 any one who wishes to form an independent judgment on this subject cannot 

 dispense with a thorough study of the skeleton of man and of anthropoid apes 

 and that sceptical phraseology will not do service instead. This, in judging 

 the colours in butterflies as in other matters, is in the majority of cases simply 

 overlooked for the sake of convenience. 



The study of colour evolution invariably indicates that red must have been 

 the original pigmental colour, in the sense of mature colour as stated. But 

 this is not all. Mayer in treating of the " Quantitative Determination of Pig- 

 mental colors " states " to have analysed the colors of many butterflies by means 

 of the spectroscope and also by Maxwell's discs ", and that in this manner 

 he has " determined that the vast majority of the colors found in Lepidoptera 

 are impure; that is to say, they contain a large percentage of black and that 

 the so-called " blacks " found in butterflies, are rarely jet-black but almost 

 always only deep shades of brown " . Thus, for instance, he found in the 

 glaucous green of Colaenis Dido 29% black and in addition 24 "/o vermilion, 

 in the sepia-brown ground colour of Cercyonis Alope 71 "/o black and 21.5 "/o 

 vermilion ; in the tawny rufous colour of wings of Mechanitis Polymnia 

 4670 black, 40 "/o vermilion, 1470 lemon-yellow; and in the rufous red patch 

 on the upper surface of the fore- wings of Heliconius Melpomene 2 7 ^o black, 

 66.5 "/o vermilion, 6.5^0 lemon-yellow. In all these cases, therefore, the colours 

 are mixtures of red and black of which red constitutes a very considerable 

 portion and sometimes also yellow, all of which, therefore, completely accords 

 with the theory of colour evolution of an original red colour with the gradual 

 increase of black, and sometimes fading te yellow. Whence otherwise comes 

 all this red and why is it thus mixed with black? This is supplemented by 

 what Mayer further states about his Spectrum ana/ysis of colors oj Lepidoptera, 

 which leads him to the conclusion that " in general the colors of the wing are 

 not simple but compound ; that is to say, they are made up of a mixture of 

 several different colors" and in these red and yellow frequently occurred; it is 

 worthy of note in this connection that he found that " the spectrum of the rufous 



