of the wing becomes very insignificant and even almost disappears. In the 

 above mentioned museum there are also still four old specimens whose under- 

 sides show a much brighter and darker yellow, as occurs also in this species 

 in other islands, and which bear the label of Java : as I do not know anything 

 about where they have been found and as they differ strongly from all the 

 above mentioned Java specimens, I dare not yet class them as such. The 

 specimens figured by Cramer, are none of them from Java. 



Indeed the Corva form must point out a stadium of the evolutional 

 increase of the black pigment in the same manner as this shows out in the 

 form LicHENOsA Moore from continental India, being in Java the most com- 

 monly met with condition of this species, for though there were found 

 individuals of the same colour in which that black is less extended and less 

 intense of colour, yet they must be reckoned among the Corva forms ; there are 

 also, as the above named specimen of Soukaboumi shows, transitions between 

 the one and the other. So one stands here before the ever embarrassing 

 question : are those light-coloured specimens to be considered as individuals 

 in which the evolutional increase of the black pigment has not yet appeared, 

 or as such in which it has already stopped and is followed again by a 

 diminishing of colour. For this last supposition might plead the fact that also 

 with those individuals with which the increase of the black seems to be 

 strongest, the upper-side of the d" is much whiter than that of the 9, which 

 agrees with what is found in other Pieridae, such as for instance Thyca 

 Hyparete L. and T. Peribaea Godx., where this doubtlessly points to a condition 

 in which the black pigment is vanishing and wherein the (5 is more advanced 

 than the 9. And also, that in the light-coloured 9 specimens the peculiar deep 

 yellow relict-spot on the underside at the base of the hind-wings, is already 

 quite gone, though that still shows out very strongly in the 9 in which a 

 strong extension of the black is present; for this does point, indeed, to the 

 fact that in the firstnamed a process of etiolation has operated vigorously. 

 But, after all, this is not of great significance, as both evolutional processes, the 

 one that makes the yellow vanish, and the other the black pigment increase 

 and diminish, proceed each independently. On the other hand the fact that the 

 light specimens are only met with here and there, just the same thing, indeed, 

 as is going on with Thyca Belisama regarding the form Belisar, and in 

 Callidryas Pomona F. regarding the form Catilla Cram., is a strong indu- 

 cement to make one think of remains from an older evolutional form in those 

 light individuals too. This supposition seems to be confirmed also by the 

 circumstance that both the light specimens caught at Batavia were got there 

 in the dr)' season, just as in the case with individuals less advanced in colour- 



