1901.] L. de Niceville — Butterflies of the subgenus Tronga. 21 



Java, godartiiy Lucas. 



Philippines, snellen% Moore. 

 ,, godartiiy Lucas. 



From the list above it would appear that Crastia does not beai' out 

 my theory at all. Under core I have placed cora, Hiibner, and vermi- 

 culatUy BuMer, as these names represent the dry- season form of the 

 species. T have also added nlcevillei, Moore, which comes from the 

 Sunderbans, near Calcutta. Many years ago four specimens of the 

 *' species " were given to me, taken in February, and I set them down 

 to be rather unusually white examples of the dry-season form of core 

 (cora-\-verr)iiculata). Two of these I gave to Colonel Swinhoe, and 

 Dr. Moore described them as Tro7iga nicevillei in Lep. Ind., vol. i, p, 77, 

 pi. XX. The male has no sexual brand in the submedian interspace of 

 the forewing, this brand, however, is often obsolete in G. core, and is not 

 a character of much importance. The wings also are broader than in 

 typical G. core. In spite of these obvious differences, I am still of 

 opinion that Tronga nicevillei is nothing more than tlie dry-season form 

 of Grastia core found in tlie swamps of the Sunderbans. I cannot 

 believe that an absolutely distinct species of Euploea is alone to be 

 found in a very limited area of recently formed alluvial land attached 

 to the mainland of Bengal. Except for this " species " India proper 

 and Ceylon is each inhabited by only a single species of Grastia. 



We now come to Burma, where godartii, Lucas, of which siamensis, 

 Felder, is an undoubted synonym, is the dominant form. With it is found 

 layardi, Druce, of which binghami, Moore, is a pure synonym. In this 

 form the pale violet apical area to the forewing on the upperside in both 

 sexes is absent ; but this feature is not constant, and intergrades between 

 true godartii and true layardi are occasionally found. But in the extreme 

 north of Burma on the coast at Akyab, at Rangoon, and in Upper 

 Tenasserim in Central Burma at Hatsiega is found subdita, Moore, which 

 is the type and only species of Moore's genus Mahintha. The only 

 specimens of this form that I have seen are from Akyab and the 

 Arakan Hills, the latter locality being rather uncertain, as my speci- 

 mens did not reach me direct from the collector but through a third 

 person. These examples do not quite agree with Dr. Moore's figures of 

 subdita from Akyab, (Lep. Ind., vol. i, pi. xxix), being less broad in the 

 wing. As a species I do not consider it to be distinct from layardi, which 

 again equals godartii, although its wings are a little broader than typical 

 specimens of the last-named species. It bears the same relation to 

 godartii that nicevillei does to core. In Upper Burma (Akyab, the Arracan 

 Coast, and at Rungamutti in the Chittagong district) E. core has been 

 obtained singly. 



