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In many places this species is not at all rare, but far less common than the 

 preceding one. It has probably originated from the same original species as 

 T. Hecabe L., with this difference, however, that the relics of pigment on the 

 under-side which still show in this latter species as brown spots, have for the 

 greater part been concentrated in T. Sari Horsf. into one large spot near the 

 apex ot the fore-wing. This spot ending towards the middle of the wing more 

 or less triangularly, is distinctly separated from the rest of the surface of the 

 wing and fills up this apex entirely, which is never the case in such specimens 

 of T. Hecabe L. mentioned before, as show at the same place an almost 

 similar spot. It is, moreover, in one specimen larger than in another; in a 

 few specimens I also found lower down on the same wing near the dorsal 

 margin another small brown spot. In the shade of the yellow in this species 

 which sometimes approaches pale orange and sometimes almost pales into white, 

 the same evolutionary dissimilarity prevails as in T. Hecabe L. The outer 

 margin on the upper-side of the hind-wings also shows the same sexual difference 

 as in this species. All the caterpillars and pupae that I have seen were green 

 without exception, though the shape did not differ from those of T. Hecabe L., 

 but the head of the larva of T. Sari Horsf. always keeps that general colour 

 of the body. Therefore it seems to me that the difference of these two species 

 has only arisen from the divergence of the first-mentioned from the common 

 original form, when the change of the colour of the caterpillar's head has also 

 begun. It seems that at that epoch a period of evolutionary change of colour 

 began for some of those caterpillars, which was not the case, however, with a 

 number of other caterpillars of the same original form, which have thus remained 

 unchanged, and that the imagines issued from each of those two categories of 

 caterpillars have since followed each their own way, too, in the course of 

 colour-evolution, which has brought about a separation of the two species. 



In T. Sari Horsf. this process revealed itself as the concentration of the 

 brown of the under-side into the apex of the fore-wings, at the same time with 

 some increase of the black pigment, which therefore does not yet exist in the 

 form Hecabe, though a tendency to follow the same way of evolution is also 

 clearly obvious in them. One may presume that the cause of this separation 

 has been the circumstance that a certain number of those caterpillars did not 

 confine themselves anymore to their original foodplant, but also began to feed 

 on other leaves, which difference of food may have had an influence on their 

 constitutions, that showed itself in a tendency to evolutional change. For, 

 indeed, I did always find the larvae of T. Sari Horsf on one plant only, 

 namely on the leaves of the jengkol (Pithecolobium Bigeminum Mrt.) on which, 

 as has been already said, those of T. Hecabe L. also occur, but these latter 



