COLOEATION AFFECTED BY THE ENVIRONMENT. 51 



at all of the ordinary character, but merely an irregularly 

 shaped, dull whitish blotch, containing a very indistinct small 

 brown mark. Vanessa, urticm and polychloros were similarly 

 treated : the latter produced no peculiar-looking specimens, 

 excepting that the ground colour was darker than in ordinary 

 bred specimens. The urticm, in spite of their starving, came out 

 nearly the natural size. Many have a thick black nervure in 

 the centre of the wing, also a brownish patch between the 

 middle costal spot and that in the inner margin ; and the dark 

 margin round the wings is wider than usual. The effects of 

 starving these three species would therefore appear to be 

 similar, as far as the causing of dark spots, patches, etc., goes." 



The change of colour in canaries when given red pepper, 

 and in certain parrots when provided with the fat of particular 

 fishes, are instances that are quoted in every book dealing with 

 these effects. There are even dealers in animals who have got 

 the reputation of being able to " colour up " birds such as the 

 flamingo by judicious feeding. 



Another remarkable instance of the apparently direct effects 

 of food in producing colour change was originally put forward 

 by Darwin, who obtained the information from Moritz Wagner. 

 It has been referred to by Prof. Mivart,* and also by Mr. 

 Lloyd Morgan. t " A number of pupee were brought' in 1870 

 to Switzerland from Texas of a species of Saturnia widely 

 different from European species. In May 1871 the moths 

 developed out of the cocoons (which had spent the winter in 

 Switzerland), and resembled entirely the Texan species. Their 

 young were fed on leaves of Juglans regia, (the Texan form 

 feeding on Juglans nigra), and they changed into moths so 

 different, not only in colour, but also in form, from their 

 parents, that they were reckoned by entomologists as a distinct 



* " On Truth," p. 378. t " Animal Life and InteUigence," p. 163. 



