some British East African Buttcrfiics. 499 



the species of Euralia, being generally seen sitting on the 

 outer leaves of trees, and the males being very fond of 

 pursuing each other with great activity. It is, however, 

 frequently to be found at rest on tree-trunks, and I have 

 observed the female settled with its wings pendent, and in 

 this position bearing a very strong resemblance to the 

 Danaine model. I have little doubt that this species is 

 specially protected and a Miillerian mimic. The facts 

 stated about the allied E. tiberius (p. 501) are equally true 

 of tvahcfieldi. 



[Taveta, July 5, 1905. They are very fond of chasing 

 each other round and round and have a very graceful 

 floating flight, which no doubt accounts for their becoming 

 mimics of A. dominicamos, of which the flisrht is somewhat 

 similar. The male generally settles on tree trunks, but I 

 have seen the female more than once settle on a branch or 

 twig with its wings hanging down exactly after the manner 

 of A. dominicanus, to which it bears a strong resemblance 

 on the wing.] 



Fapilio dardanus, Brown, sub-sp. tibullus, Kirby, female 

 form hippocoon, F. (Plate XXVI, fig. 2). This is by far 

 the commonest form of the female and is of very frequent 

 occurrence. It is readily distinguished during flight by 

 the prominent sub-marginal spots in the dark border of 

 the hind-wing. I have met with this form in some abund- 

 ance as far away as Nairobi in the Kikuyu country, and it 

 remains the dominant variety of the female from this 

 locality westward to the Atlantic coast. 



1. The Relative Abundance of the members of the Amauris 



niavius dominicanus-centred Combination. 



In my experience Eitralia usambara is the only really 

 rare member of the association, and the only one with a 

 restricted range. All the other constituent species have a 

 considerable range in the Coast district. The relative 

 abundance of the different species varies considerably in 

 different localities. At Taveta, for instance, the primary 

 model, A. niavius dominicanus, outnumbered many times 

 all the others ; while at Rabai its dominance was by no 

 means so well marked. 



b. Amauris ochlea-centred Combination. 



In addition to the Danaine model this combination con- 

 tains the following species, of which all except Euxanthe 

 TRANS. ENT. SOC. LOND. 1908. — PART III. (DEC.) 33 



