Vlt 



have been produced, that which occurs in the genus Euploea and that which 

 is to be observed in the genera Hestia, Ideopsis, and Danais. In Euploea 

 the black has entirely fused with the original red in such a manner that the 

 peculiar more or less dark red-brown, characterising this genus, has been 

 produced ; in some species, however, the red in this colour fusion has remained 

 so predominant in some spots that much of the original pigment has distinctly 

 been retained. In some species white dots make their appearance on this red- 

 brown, in others they become more numerous and larger, increasing to large 

 spots or even horizontal or vertical streaks; some portions of the wings, 

 especially along the margins, even become completely white ; this occurs most 

 markedly in the individuals of species living in the K6 islands, whose members 

 in other regions have not yet reached such a stage in the process of loss of 

 pigment. Other Euploeas fade more gradually ; thus E. Browni Godm. Salv., 

 occurring in the east of New Ireland [New Mecklenburg], has practically 

 become entirely white, while of the former brown colour only small patches remain 

 on the under surface. The production of these white dots is evidently due to 

 no other cause than that in the process of colour evolution certain of the scales, 

 originally filled with red pigment, have reached a stage where the pigment, 

 fading gradually at first, has totally disappeared and in this manner the scale, 

 filled with air, produces the intense white colour, peculiar to such scales; the 

 further this process continues and the more the number of scales filled with 

 air increases, the larger and more numerous of course do the white spots 

 become. Whereas in some butterflies, as the Pieridae, after the disappearance 

 of the pigment the wing scales drop, sometimes causing a glassy appearance 

 at those portions of the wings, this does not appear to be the case in other 

 butterflies, where the scales, now devoid of pigment, become filled with air, 

 producing the intense white colour much brighter than the pigmental white of 

 the Pieridae, which occurs in many butterflies and especially in Danaidae. 



It is very important in this connection to observe how these white dots 

 increase to form larger spots and even white streaks, in which case, therefore, 

 such spots do not arise from white streaks, as has been assumed in a well 

 known theory to be a fixed rule; also that in the production of such streaks 

 and spots in the species of some definite district a certain plan cannot be 

 denied, which goes to prove that this is also governed by influences peculiar 

 to the districts in question. 



In the genera Hestia, Ideopsis, and Danais, however, this so universal 

 fusion of the black with the original red pigment has not taken place. In 

 these black entirely replaces the original colour in some parts, especially in the 

 apex of the fore wings and is diffused only partially over the remainder of 



