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Leyden museum, from which it differs little and apparently only evolutionally. 

 Now it is, however, but little probable that such an influence should have attacked 

 the under-side only. I have had this Leyden specimen figured, (PI. II, fig. 4^) 

 as well as another small specimen, (PI. II, fig. ^d) also a cT from the same 

 museum, also old and not known where it has been found, the upper-side of 

 which still shows a particularly dark orange, darker than is the case in the 

 form Belisar, and in my opinion corresponding with the dirty orange which, 

 according to Staudinger, characterizes the upper-side of his form Erubescens. 

 In the collection of Dr. Martin at Diessen am Ammersee I also found a $, 

 whose colour on the upper-side was very dark yellow and on the under-side 

 approached closely the form Erubescens. But this specimen also, acquired 

 from the Sommer collection, was very old. Yet, if anybody were to admit that 

 the said alteration has been caused by some chemical influence which had 

 affected these specimens in their dried state, he would have to do so also with 

 respect to the above-mentioned specimens Staudinger and Fruhstorfer, though 

 the latter at least is certainly not old and well preserved, which renders the 

 inworking of such an influence but little likely. Then the form Erubescens 

 should be suppressed. It is with the view to promote the solution of this 

 question that I publish the figures of the two doubtful colour-forms of the 

 Leyden museum. 



For the rest the orange on the upper-side of the d" has already turned into 

 white, but among these there are sometimes found some in which the evolution 

 has not yet proceeded so far and whose upper-side therefore, especially of the 

 hind-wings, is not yet quite white, but as a transition more of less lemon-coloured. 

 (PL II fig. 4 f.) The under-side of the wings of these (f does not really differ 

 from that of the above mentioned old form Belisar, except that the under-side 

 of the fore-wings is not strongly irrorated with yellow as is the case in the 

 aforesaid form; gradually, however, the orange of the hind-wings and of three 

 short, but rather broad streaks near the apex of the fore-wings is bleaching, so 

 as to become at last a pale yellow on the hind-wings and even white in the three 

 above-mentioned streaks. This stage of colour-evolution is connected by many 

 transitions with the former — the Belisama Belisama of Fruhstorfer (PI. II, 

 fig. 4^) — but is differentiated from this one in the most advanced specimens 

 as the form Nakula Smith or Vestalina Stdgr. So the specimen figured by 

 Grose Smith as the cf of the form Nakula, in which the under-side of the 

 hind-wings is already yellow, but the streaks near the apex of the fore-wings 

 are not yet white, belongs to the transitions just-mentioned. Staudinger mentions 

 the form Vestalina from Magelang in C. J. and I found it indeed very common 

 at Jogjokarta, situated not far from that locality; but also in E. J. this form 



