212 Mr, S. A. Neave : some lionomic 



the confluent edges of their distribution is of remarkable 

 interest* It should help to impress upon systematists 

 the importance of carefully considering the question of 

 geographical races of species before making new species 

 on slight differences. 



Mimetic Groups with Danaine Models. 



The black and white Amauris niavius, Linn., forms the 

 model for an important group of butterflies of many families. 

 It is evidently very abundant on the shores of the Lake, 

 There are 118 specimens in the Wiggins Collection. 



The group comprises : — - 



Euralia anthedon, Doub, et Hew. (14). 



Hypolimnas montcironis, Druce (4 (^ ^, 8 $ $), of which 

 the ^ only is mimetic, 



Papilio dardanus ^, f. Mppocoon, Fabr. (8), mostly from 

 the eastern side of the Lake. The ,^ ,^ of dardanus (46) 

 were common nearly everywhere, 



Elymnias hammakoo, Westw. (7), all from the Western 

 districts. 



In all these forms the resemblance to the model is 

 remarkably good, the distribution of white markings on a 

 black or dusty ground faithfully follows those of the model 

 and dift'ers in much the same way from the South and East 

 African mimics (II. waJilhergi, P. cenea, hippocoonoides, etc.) 

 of A. niavius dominicanus as the two models do from 

 each other. 



The $ ^ of PIa7iema godmani, Butler (2), with the recently 

 described Pscudacraia tirikensis, mihi (3), resenibling it in 

 an astonishing manner, form a subsidiary black and white 

 group within the larger assembly having niavius as its 

 model. This is, perhaps, especially the case when the 

 insects are on the wing. At rest the Planema, and the 

 Pseudacr/ea closely following its model, present the 

 character so common in the larger Ethiopian Acrxinm 

 of a black-spotted chocolate-brown triangle at the base of 

 the hind wing on the under surface. The influence of this 

 character on other forms and of other forms on it has 



* Professor Poulton has already called attention to the case of 

 ^1. niavius in his Presidential Address to the Entomological Society 

 J904. Trans. Ent, goc. 1903, p. xciv, 



