SYNONYMY OF SOME SPECIES OF INDIAN PIERINZ. 513 
Mr. Butler’s oversight is due to the fact that his original 
specimen like most other forms of TZ. silhetana is pale yellow, 
and therefore rather similar to females of the hecabe group, while the 
second specimen is of the usual darker yellow of 7. excavata, and, 
as the apical markings on the underside of the two specimens 
are very similar, they being the corresponding forms of two different 
species, he was led to believe they were the same species. As these 
apical markings on the underside are the distinctive characters on 
which so many described forms have been based, and as it has not 
been generally recognised that these markings are purely seasonal, no 
doubt the mistake was a very natural one; it is, however, unfortunate 
that he overlooked the sexual glandular streak on the underside of the 
forewing, which is present in both specimens. It will therefore be 
seen that the Durbunga specimen, which is not absolutely typical 
T. excavata, has no name. Will Colonel Swinhoe oblige ? 
The next three forms, 7. hecabe, T. hecabeoides, and T. nicobarensis, 
are absolutely identical, and there is no doubt that if the specimens of 
the three forms in the British Museum were mixed together no one 
would be able to re-separate them as at present arranged, 
T. iempletonii has the marginal band of the forewing rather less 
dilated at the outer angle than in typical T. hecabe, but otherwise does 
not differ from it. 
T. curtosa, of which the type is the sole known specimen, appears 
to be a “sport” of T. hecabe. 
T. simulata is inseparable from T. eacavata, which is the ordinary 
dry-season form of 7. hecabe. 
T. fraterna differs in the marginal border to the hindwing being 
obsolete, which is probably due to its dry habitat. 
T. swinhoci, T. patruelis, and T. purreea are slight varieties of 
T. excavata, and occur with it throughout its range. The first two are 
inseparable the one from the other, and the third is hardly more 
distinct. 
Of the next five forms, T. irregularts is an exact synonym of 
T. fimbriata, and T. asphodelus of T. narcissus, which is slightly 
smaller than J. irregulars ; while T. simplex differs slightly in the 
shape of the marginal band of the forewing. They are all almost 
certainly only extremes of the dry-season form of 7. hecabe. 
