13 



7- Paulina Cram. (PI. I, fig. 5 a, b, c). 



Cramer, ///. 2 i //. i 10 £", /^ 9 (i779) Pap. Paulina. 



BorsDUVAL, Spec. Gen. I p. 480 6' (1836) Pieris Albina. 



Snell. v. Voll., Mon. d. Pier. /. 44 (1865) „ „ 



Staud., Exot. ScJim. />. 30//. 17 (1884 — 88) Tachyris „ 



Semper, Sclimett. d. P//iL I p. 246//. ^o fig. 6—8 cT 9 



(1886 — 92) Appias „ 



Bingham, Fatma of Br. India p. 210 (1907) „ Paulina. 



Pieris Albina Bsd. is the c? of P. Paulina Cram. The Appias Albina 

 of Bingham (II p. 212), however, is not this species but Pieris Rouxii Bsd. 



W. J. A few times at Depok (95) and also in the Gedeh moutains. 



C. J. In the province of Rembang. 



E. J. Pouspa (630) and Tosari (1777) in the Tengger mountains, Banjouwangi. 



The study of this butterfly, especially the comparison of its colour and 

 pattern with those of the very closely related species Pieris Amasene Cram, 

 is very important as to a just understanding of the phenomenon which I 

 call the colour evolution. The upper-side of the 9 of both species are very 

 much alike, there is only a slight difference in the manner in which the black 

 has extended itself The (S', on the contrary, differ clearly. But now the 

 female so-called variety of P. Paulina, figured on pi. I fig. '^b, shows agains 

 clearly the same system of colouring as the cf of P. Amasene. How is this 

 to be explained? Only by means of the knowledge of the said phenomenon 

 does this seem possible. Both closely related species follow the same direction 

 in that evolution. The 9 of both species have kept pace with each other in 

 this respect and, therefore, are nearly alike but for a slight difference. But the 

 evolution does not always keep pace in both sexes, and so the ^ of P. Paulina, 

 which have already lost all the black, have evidently proceeded much further 

 than the cT of P. Amasene; so that the figuration of colour and markings of 

 this sex differs in the two species. Not only with regard to species and sexes, 

 however, does this evolution not continue equally, it does not happen either 

 with respect to individuals of the same species and the same sex; so that also 

 some individuals alter less than others. Such a one that has remained behind, 

 is the said 9 variety of P. Paulina ; this one is still in the same stage, which 

 the other 9 of this species have already left, and for this reason resembles the 

 cf of P. Amasene, which are all still in this less advanced stage in the same 

 process of evolution. 



The condition of extension of the black on the upper-side of the cf of 



