158 MIMICRY IN N. AMERICAN BUTTERFLIES 



between these Old and New World Danaines, and 

 also the validity of the genera created by Moore. 1 

 Such a comparison had already been partially made 

 by Kothschild and Jordan, who in 1903 published 

 the conclusion that Limnas and Tasitia cannot be 

 generically separated. 2 I therefore wrote to my 

 friend Dr. Jordan, asking if he would kindly 

 extend his survey over all the four so-called genera. 

 He found that in Salatura genutia and Anosia 

 plexippus, having larvae with two pairs of fila- 

 ments, 3 the male genitalia are of the same type ; 

 while hi Limnas chrysippus and Tasitia berenice, 

 having larvae with three pairs of filaments, these 

 genitalia are of a second type. The final opinion 

 of this distinguished authority on the relationships 

 between the Rhopalocera, was given in the fol- 

 lowing words 4 : 



' It appears to be certain that Anosia plexippus does not 

 stand apart from the others. Therefore, if Tasitia berenice, 

 Limnas chrysippus and Salatura genutia are placed in one 



1 Proc. Zool. Soc. Lond., 1883, 201. 



2 Nov. Zool. vol. x, Dec., 1903, 502. 



3 Dr. Jordan was at first inclined to think that Anosia plexippus 

 should he separated generically, basing his conclusion in part on 

 the larval characters (Trans. Ent. Soc. Lond., 1908, 450). A more 

 extended review of the Tring material pointed in the opposite 

 direction, and Dr. Jordan wrote on December 10, 1908, as follows: 

 ' I find from our specimens [of preserved larvae] that 



(1) in Euploea (in the wide sense) there are 4 pairs of filaments, 

 or three (the 3rd being absent), or two (the 3rd and 4th being 

 absent). 



(2) In Danaidae, incl. of Anosia & Limnas, there are 3 pairs (the 

 3rd of the 4 pairs of Euploea being absent), or 2 pairs (the 2nd 

 and 3rd being absent). I find that, for instance, genutia and 

 purpurata have 2 pairs only, like plexippus. The larva therefore 

 does not furnish any argument for separating plexippus as a 

 genus.' 



* In a letter to the author, dated December 15, 1908, 



