Eastern PieridcB. 359 



thirds black, and one-third yellow, the division not being clearly 

 defined as in T. isse. 



Female. — Above: basal half of the wings pale yellow, the rest 

 black without apical spots ; beneath, the apical spots are very 

 small, the black border of the uppers is shaped nearly as in the 

 male, the part near the outer angle being white ; the lower wings 

 have the black extending a little further up, the band of orange 

 spots very small', and the anal angle rich orange. Size the same 

 as T. isse. 



Hab.— Bourn (Coll. Wall.). 



This species differs from T. isse in almost exactly the same 

 points that T, philolis differs from T. philyra, — a very curious fact 

 in connexion with the laws of variation, since it shows a definite 

 modifying influence in particular localities, which effects the same 

 changes in distinct species. I may remark also that in both cases 

 the hind wings of the Bouru forms are more elongate than those 

 of Ceram and Amboina. 



* * * * *' * Beneath : upper wings black, lower wings yellow, 



nervures not dilated. 



48. Tliijca chrysomelcena, Vollenhoven. 



Pieris chri/somelcetia, Voll. Tijd. voor Ent. 1866, p. 57, pi. i. 



f. 12. 

 Hal). — Kaioa Island (Moluccas). (Leyden Mus.) 



This very beautiful species will come at the head of the dori- 

 viene subdivision, and is most nearly allied to T. echidna. It 

 was obtained by the late Herr Bernstein in a small island, where 

 I had myself captured several new species of Coleoplera, but, 

 perhaps owing to the time of year, very few Lepidoptera. 



49. Thyca echidna , He wit son. 

 Pieris echidna, Hew. Ex. Butt. vol. ii. Pieris V. f. 35, 3G. 

 Sab.—Cemm (Coll. Wall.). 



I obtained only a single specimen of this distinct and beautiful 

 species in the island of Ceram. 



50. Thyca hippodamia, n. sp. (PI. VIII. fig. 1,^.) 

 Male. — Above, w^hite, the colours of the under surface showing 



