Dr. A. G. Butler on Lepidoptera from Nyasa. 71 



11. Junonia pelasgis. 



Vanessa pelasgis, Godart, Enc. Mth. ix., Suppl. p. 820 (1823). 

 Var. Junonia chapunga, Hewitson, Exot. Butt, iii., Jun. pi. i. figs. 2, 3 

 (1864). 



cJ, Kwereru Hill, Deep Bay, April 22nd, 1895; ? , foot 

 of Jakwa Mountain, Nkamanga, Jan. 28th, 1895. 



" Dusky Tortoiseshell. Impossible almost to take a perfect 

 specimen " (R. C.). 



The specimens now sent completely link /. chapunga to 

 J. pelasgis. 



12. Junonia cuama. 

 Junonia cuama, Hewitson, Exot. Butt, iii., Jun. pi. i. figs. 4, 5 (1864). 



Kondowi, Lower Nyika, April 6th, 1895. 



I have recently been assured that this is an extreme dry- 

 season form of J. simia, Wllgr., and that my J. Trimeni is 

 a form produced between the wet and dry seasons. Before 

 this can be accepted it will have to be proved by breeding, 

 for the evidence offered by dated specimens distinctly con- 

 tradicts the assertion. I am beginning to have very serious 

 doubts as to the reliability of the evidence upon which many 

 of the so-called " seasonal forms " are associated. In the 

 Museum series we now have twelve examples of J. cuama, 

 half of which are labelled with the dates of capture January, 

 April, September, and December. Of J. Trimeni we have 

 nine, all dated, as follows : January, February, July, De- 

 cember. Of J. simia we have fifteen, of which five are 

 dated January, April, July, and December. Therefore it is 

 absolutely certain that the supposed extreme dry- and wet- 

 season forms occur in perfect condition simultaneously in 

 January, April, and December, and that the intermediate and 

 wet-season forms occur together in January, July, and De- 

 cember. Whenever we have received carefully dated collec- 

 tions from scrupulously accurate collectors I have invariably 

 found that they tended to disprove most conclusively the 

 assertions incessantly made as to seasonal di- or polymorphism. 

 In hardly any instances are these assertions supported by 

 careful experiments in breeding ; but, so far as 1 have been 

 able to judge, they appear to have been based solely upon the 

 dates at which certain forms happen to have occurred in 

 quantity. We will, for the sake of example, assume that 

 Vanessa urticce occurred in quantities in June and V. poly- 

 chloros took its place in October (I do not pretend that they do 

 so) : the exponent of seasonal dimorphism would immediately 

 declare that V. urlicce was the dry-season form of V. poly- 



