82 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol. XVI 



allied Indian species from the Himalayas or even Sikhim. The follow- 

 ing genera will serve as examples : — 



7. Cyaniris. 



8. Loxura. 



9. Appias. 



10. Nepheronia. 



11. Troides. 



Again, without exception, all the local races of Ceylon butterflies, 

 though belonging to the above group, are darker in colouration than 

 their allied Indian relatives ; as instances I may give — 



1. Hestia jasonia. 



2. Euploea (in partj. 



3. Mycalesis patnia. 



4. Elymnias fraterna. 



5. Charaxes psaphon. 



6. Limenitis calidosa. 



7. Cethosia nietneri. 



8. Cirhochoroa lanka. 



To account for this is by no means easy, and I doubt whether an 

 entirely satisfactory explanation is at present forthcoming. One point 

 seems clear, and that is that all the species are influenced by some 

 agent, having a continuous and universal action on them. Knowing as 

 we do that changes of temperature, rainfall and the like have a marked 

 influence on certain species, causing the so-called " wet " and " dry " 

 season forms, it seems reasonable to assume that climate is a marked 

 factor in causing this intensity of colouring in the Indo-Ceylon group, 

 and if this is the case it seems to me a logical conclusion that climate has 

 had a great deal more to do with the colouration of butterflies generally 

 than some entomologists are ready to allow. So far as our knowledge 

 goes at present it is impossible to say at any rate among tropical 

 butterflies exactly how much heat or moisture is necessary to produce 

 a " wet " or " dry " form, but undoubtedly there is a good deal of 

 evidence to show that heat and moisture tend to produce certain 

 colours and intensify, or reduce, the colouring of a species according 

 to its geographical and climatal conditions. 



Deep blue or purple in a tropical butterfly is almost invariably 

 indicative of a habitat of deep jungle amidst sombre surroundings with 

 a elimate of heavy rainfall and a high temperature throughout the year, 

 as for instance, Thaumantis diores. The deep blue of Kallima limborgii 

 has doubtless been produced by the above conditions. 



It may be assumed that the various species or local races of the 

 orange-banded Himalayan and Burmese Kallima are derived primarily 



