x] MIMICRY AND VARIATION 135 



Protogonius, and other forms. In Eastern Brazil the 

 predominant pattern is one characterised by a yellow 

 band across the hind wing and a white or yellow apical 

 fore wing marking (cf. PL XV, figs. 3 and 8). Here 

 also, with the exception of the Perrhybris, all the 

 various genera which figured in the last group are again 

 represented. It is true that the members of this 

 second group are regarded as belonging to different 

 species from those of the first group, but as species 

 here are made by the systematist chiefly, if not entirely, 

 on the colour pattern this fact may not mean much. 

 Passing now to Ega on the Upper Amazons the general 

 ground colour is a deep chestnut purple and the apical 

 area of the fore wings presents a much mottled appear- 

 ance (cf. PI. XV, figs. 4 and 9). In this group again 

 we find represented the different genera found in the 

 other groups, the only notable absentees being Eresia 

 and Perrhybris. Lastly in Ecuador, Peru, and Bolivia 

 the general pattern scheme consists of orange-tawny 

 markings on a black ground (cf. PL XV, figs. 5 and 10). 

 This group differs somewhat in composition from the 

 preceding in that it contains no Pierid and no Danaid. 

 On the other hand its numbers have been strengthened 

 by the accession of a Papilio, an Acraea, and two 

 species of the Satyrid genus Pedaliodes. Certain writers 

 have seen in the theory of mimicry the only explanation 

 of these peculiar geographical pattern groups. The 

 fashion is in each case set by the most abundant form, 

 generally an Ithomiine of the genus Melinaea. The rest 

 are mimics of this dominant species, either in the 



