48 NEW-WORLD MIMICS [ch. 



philenor. Hence it is of advantage to them to have 

 even a chance of being mistaken for the more obnoxious 

 philenor, and so the one has come from the black 

 and yellow Swallow-tail pattern and the other from 

 the white-banded arthemis form to what they are, 

 i.e. more alike to one another than to philenor. They 

 now form a Mullerian combination for mutual protection 

 along with the dark females of glaucus and asterius. 

 But they are themselves still moderately distasteful 

 so that it is to the advantage of the female of Argynnis 

 diana to mimic them. Whether they are all on the 

 way to resembling philenor more closely, or whether 

 they have sufficiently vindicated their inedible proper- 

 ties and are now stationary, it is for the future to 

 reveal to posterity. Lastly we have the view that 

 these different species have attained their present 

 coloration entirely independently of one another, 

 and that we are not here concerned with mimicry 

 at all. Since the sole evidence available at present 

 is that based on general appearance and geographical 

 distribution, the view taken of this case must rest 

 largely upon personal inclination. 



Though the cases just quoted are only very pro- 

 blematically mimetic, N. America has yet several 

 examples of resemblance between distantly related 

 forms as close as any that occur in the tropics. In 

 this region are found two species of the genus Danais — 

 D. archippus occurring all over the United States 

 and reaching up northwards into Canada, D. berenice 

 found in the South-eastern States, e.g. in Florida, 

 where it is said to be more abundant than archippus. 



