22 OLD-WORLD MIMICS [ch. 



Simple mimicry, explicable, at any rate in theory, 

 on the Knes laid down by Bates, is a phenomenon of 

 not infrequent occm'rence in tropical countries, though 

 rare in more temperate lands. In each of the three 

 great divisions of the tropical world we find certain 

 groups of butterflies serving as models, and being 

 mimicked by butterflies belonging as a rule to quite 

 different groups. Speaking generally the models of 

 any given region are confined to a few groups, while 

 the mimics are drawn from a greater number. In Asia 

 the principal models belong to the Danaines, the 

 Euploeines, and to a group of swallow-tails which from 

 the fact that their larvae feed on the poisonous Aris- 

 tolochia plant are generally distinguished as the " Poison- 

 eaters," or Pharmacophagus group. Of these the 

 Danaines and Euploeines are closely related and have 

 much in common. They are usually butterflies of 

 medium size, of rather flimsy build and with a some- 

 what slow and flaunting flight. In spite, however, of 

 their slight build they are toughly made and very 

 tenacious of life. Most butterflies are easily killed by 

 simply nipping the thorax. There is a slight crack 

 and the fly never recovers. But the collector who 

 treats a Danaid in a way that would easily kill most 

 butterflies is as likely as not many hours after to find 

 it stiU alive in his collecting box or in the paper to 

 which it may have been transferred when caught. 

 They give one the impression of being tougher and 

 more "rubbery" in consistence than the majority of 

 Lepidoptera. Moreover, the juices of their bodies seem 



