422 L. de Niceville & Dr. L. Martin — Butterflies of Sumatra. [No. 3, 



Other probable synonyms are E. gopia, Moore, E. godartii, Gray, 

 described from Sumatra, and E. monina, Fabricius. During the time 

 Mr. W. Davison of the Singapore Museum was alive be devoted 

 much time and pains to no purpose in trying to separate into dis- 

 tinct species the many forms recorded by Mr. Distant from the Malay 

 Peninsula, and to this end captured many hundreds of specimens 

 of both sexes, numbers of which he sent to me. In the forests of 

 Sumatra this protean species is equally common, and Dr. Martin has 

 obtained both sexes in large numbers. He and I have quite failed to 

 split them up into separate species. Dr. Staudinger appears also to 

 have succeeded no better. Both sexes are variable, but it is in the 

 female that the variations are the greater and more puzzling. It is 

 quite easy to assign names in accordance with described species to the 

 more conspicuous varieties, but when one comes to arrange large series 

 of specimens one finds how impossible it is to divide them into separate 

 species. The only solution of the difficulty in splitting up this species 

 appears to lie in extensive breeding from the egg. Even supposing 

 the male primary sexual organs should on microscopical examination 

 disclose specific differences, the difficulty will only be half got over, as 

 the question of pairing the females with the males found to represent 

 distinct species will be quite hopeless till both are bred. I have adopt- 

 ed the oldest name for the group. Dr. O. Staudinger has taken the next 

 oldest name, which is the " Papilio " monina, also of Fabricius. E, cocytus 

 is the commonest species of Euthalia occurring in our area, and is found 

 every where except on the Central Plateau. The males are very easily 

 damaged, and seldom found in collections in an absolutely perfect state. 

 The male is doubtless mimicked on the wing by the males of Stibochiona 

 kunii-ijicltri, Fruhstorfer. 



209. Euthalia (Felderia) asoka, Felder, 



Snellen. This species was originally described from a female 

 from "Malacca interior" and Borneo ; Distant records it from Penang, 

 Province Wellesley, and Malacca. He figures both sexes, and associates 

 with the very distinct female a male with the apex of the forewing 

 rather more produced than in the males of the other species of the 

 group he retains as distinct species, and with the underside of both 

 wings unusually dark, with a broad outer pale margin to the forewing. 

 At the earnest .request of Dr. Martin I retain this species as distinct 

 from E. cocytus, Fabricius, but it is against my better judgment 

 to do so, The female is typically very distinct, as it has on the 

 upperside of the forewing a prominent band of seven sullied white 

 spots, the anteriormost sometimes divided into two spots, but joined 



