Species of the Genus Limenitis. 467 



With regard to Argynnis diana I have no further inform- 

 ation, but there is evidence that L. astyanax occurs with 

 the Papilios. Thus Scudder states (p. 287) that it is per- 

 secuted by Papilio asterius. It is possible that, as in other 

 cases which have been observed, the male asterius may 

 pursue astyanax in mistake for its own female. Professor 

 Bateson has informed me that he took astyanax with at 

 least one of the above-named Papilios (probably P. troilus) 

 and that he was greatly impressed with their resemblance 

 in the field. In fact, if I understood him rightly, his 

 general impression at the time was that he was observing 

 a single species. Mr. J. C. Moulton has recently shown 

 me six specimens of astyanax and one of the turnus female 

 of P. glaucus, from a small collection of butterflies recently 

 made at Sioux, Iowa, by Mr. C. H. Griffith. 



The relation of the turnus female of Papilio 



GLAUCUS TO (1) the PRIMARY MODEL, P. PHILENOR ; 

 (2) ITS CO-MIMICS IN THE PaPILIONIN^. 



At first sight the under surface of the dark southern 

 mimetic female of P. turnus appears to be little more than 

 that of a melanic variety in which the characteristic black 

 markings of the fore-wing can be seen in deeper pigment 

 than the ground colour. A remarkable feature is the per- 

 sistence of a pale patch of ground colour just inside the end 

 of the cell. In the non-mimetic females this very patch is 

 more or less cut off by dark pigment from the rest of the 

 pale ground colour, and it is an interesting fact that the 

 isolated ground colour should remain pale while the rest 

 has darkened. When the details of the mimetic resem- 

 blance are examined it is at once seen that the form 

 turnus is far more than a mere melanic transformation of 

 the female glaucus. There is a persistence of every element 

 that aids in the superficial resemblance to the co-mimics 

 and to the central model, jyhilcnor : — the marginal and 

 submarginal series of yellow markings of the fore- wing, 

 and the yellow marginal and deep orange submarginal 

 series of the hind-wing, and between these two series the 

 great intensification of bluish-green, margined internally 

 with bright blue. 



On the upper surface of turnus the adaptive nature of 

 the transformation is even more evident. The blackness 

 here is far more intense than on the uu<ler surfi\ce, and 

 obliterates all the black markings of glaucus, any of which 



TRANS. ENT. SOC. LOND. 1908. — PART IIL (DEC.) 31 



