Pierine Butterjlies of the Genus Tei ias. 79 



primaries more equal in width than in the type. The wet- 

 season form onlj is known. 



57. Terias tllaha. 

 $. Terias tilaha, Horsfield, Cat. Lep. E. I. C. p. 136 (1829). 



Java and Borneo. 



Our ten examples are quite uniform in character and belong 

 to an intermediate-season phase. The greater size, much 

 broader apical border of primaries, the more elongated sinus 

 in the border on the lower median interspace, and the exten- 

 sion of the inner border so as to impinge upon the discoidal 

 cell at its base render it next to impossible that this can be 

 the intermediate form of the preceding species, for we know 

 that the change from a wet- to a dry-season character in this 

 genus is usually accompanied by a decrease in the dark 

 borders of the upper surface, and never by an increase in their 

 width. When any change in size takes place, it tends 

 towards diminution of expanse in the dry season, 



58. Terias Nicevillei^ sp. n. 



I believe this to be the T. tilaha of De Nic^ville ; it is the 

 smallest species of the group j it differs in pattern from 

 T. tilaha in the slightly more regular inner oblique edging to 

 the apical border of the primaries, the slightly narrower outer 

 border of the male secondaries and the broader border to 

 those of the female ; the latter sex is also much deeper in 

 colour than in T. tilaha, being nearly as bright a yellow as 

 the male ; the under surface is similar to that of T. tilaha. 



Expanse of wings 38 millim. 



N.E. Sumatra (from Capt. E. Y. Watson's collection). 



59. Terias rahel. 

 Papilio rahel, Fabiicius, Mant. Ins. ii. p. 22 (1787). 



Borneo. 



This is the Bornean representative of T. tondana, from 

 which it differs in having the pattern of the primaries more 

 nearly like that of T. tilaha and the pattern of the secondaries 

 nearly alike in both sexes ; whereas the female of T. toininia 

 differs widely from its male in all the wings. The abdominal 

 border of the secondaries is less strongly marked than in 

 T. tomhiia. This, again, is an intermediate form in the 

 under-surface markings. 



