CALIFORNICA A RECENT MODEL 199 



south an intruder that has modified the indi- 

 genous inhabitant lorquini and has been also 

 reciprocally modified thereby. 



Limenitis in the broad sense is part of the 

 ancient northern butterfly fauna of North America. 

 It has here split up into several well-marked 

 species characteristic of the area. It is highly 

 susceptible to mimetic influence far more so 

 than any other North American group and 

 contributes the majority of the examples of 

 Mimicry from this part of the world. L. archippus 

 has been shown to be the result of a recent 

 invasion, its southern and eastern forms to be 

 still newer products of the changes in archippus 

 itself. The sensitiveness of the group is shown 

 by the fact that, in spite of this recent origin, 

 all except astyanax are most beautiful and striking 

 mimics ; and even astyanax is a better mimic 

 than lorquini. The fact that lorquini, the member 

 of so sensitive a group, is an undoubted mimic, 

 but a very poor mimic, supports the conclusion 

 that the association with its model has endured 

 for but a brief period, a conclusion also supported 

 by the diminution of the resemblance outside 

 the range of caUfornica. 



If the relationships which I have found to 

 exist in the available material in quantity very 

 insufficient for such minute comparisons if these 

 are confirmed by extensive investigations in 

 America, it will follow that the resemblances 

 between L. californica and L. lorquini will be one 



