( 325 ) 



with one variable, polj'chromatic, species, we may say that this species is in a 

 process of being evolved into a dimorphic species by the elimination of the inter- 

 mediate links. But it is surely fntile to speculate any further on this subject, 

 before we know precisely the life-history of the insects. 



However, by uniting the various North Indian and Burmese examples to one 

 species, we create another difficulty, respecting the Chinese and Malayan forms. 

 For if we assume, as we are bound to do with our present incomplete knowledge, 

 that forms like khasianus and eorax are the same species, it would only be con- 

 sistent to regard also the banded and not-banded specimens from Sumatra, Borneo, 

 etc., as individuals of a dichromatic species. This, however, we cannot do, as 

 regards the Malayan insects, because the banded Malayan forms are all well-defined, 

 being, so far as we know, constantly different from the Indian banded individuals, 

 while the not-banded extra-Indian individuals are in the male sex not always distin- 

 guishable from the Indian not-banded specimens. Therefore we think it justifiable 

 to treat the Malayan banded forms as specifically distinct, whereas we must 

 include the forms with not-banded c?c? in the same species to which the various 

 banded and not-banded Indian forms belong. The Chinese banded and not-banded 

 males we consider also to be specifically identical ; it is true, there is no complete 

 chain of intermediate specimens known, but the material in collections is so scanty 

 and shows yet so much variability that the course we adopt is the best to follow at 

 present. 



The South Indian and Ceylonese Ch. psaphon is only a geographical offshoot of 

 the species under discussion, but we treat it nevertheless as a distinct species, 

 because it is apparently always well distinguishable in both sexes from all other 

 forms. Ch. psaphon is, moreover, in so far of particular interest as the S is not- 

 banded, while the ? agrees to a certain extent better with the ? ? of the banded 

 than with those of the not-banded forms, and might therefore be called a rejwesenta- 

 tive of the banded as well as of the not-banded Malayan species. It is, however, 

 possible that a larger material from the North-West Himalayas and Nepal of the form 

 called hemana, of which we have seen only a few individuals, will contain gradations 

 from hemana, to psaphon, in which case psaphon will sink as a subspecies of the 

 variable Indo-Malayan Ch. polyxena. 



11. Charaxes polyxena. 



5 . Pap'dio Eques Achiviis polyxena Cramer, Pup. Exot. I. p. 85. t. 54. f. A.B. (1775) (China ; ? , 



mutilatfcl). 

 ? . Papilio Eques Achirus bernardus Fabricius, EhI. Syst. III. 1. p. 72. n. 223 (1893) (China) (1775) 



(China, ? ). 



cJ. Wings, upperside. Forewing : black outer area broad, at least in front, 



the black discal lunnles merged together with it, but Innnles M' — SM" sometimes 

 almost separate, occasionally obsolete ; postdiscal tawny or white interspace M- — 

 SM* seldom filled up with black scaling, the other postdiscal iutersj)aces often also 

 more or less marked, but interspace B? — R^ always very much smaller than the 

 discal portion R^ — R' of the black area at its proximal side, and situated halfway 

 between median bar R' — R^ and outer margin of wing ; discal interspaces varying 



from being bluish white to being concolorous with the basal area. Hindwing less 



dentate than in marmax and allies, tooth M' less prominent. 



Underside : discal bars SC* — SC* of forewing about a third the way between 



