514 L. de Nic^ville & Dr. L. Martin — Butterflies of Sumatra. [No. 3, 
581. Papilio ( Charus ) helenus, Linnaeus. 
Grose Smith. Snellen. Hagen. Wallace. Butler. Distant. 
Dr. Wallace separates off the Sumatran and Javan form of P. helenus 
from the North Indian form as a “ Local form b,” differing in being 
“Smaller; the third and fourth lunules from the anal angle beneath 
very small or quite absent.” Next to P. polytes, Linnaeus, and 
P. antiphus , Fabricius, this is our most common Papilio, a true inhabi¬ 
tant of the forest, found over the whole of our area, even on the Cen¬ 
tral Plateau, but most plentiful on the outer hills. The male has a 
quick and powerful flight, and frequents flowers and wet spots on forest 
roads. The female is rarer, and must be looked for in the forest when 
depositing her eggs. The larva is most common in February on different 
species of Citrus , it is superficially very similar to that of P. memnon , 
Linnaeus, but is somewhat smaller and has brownish-red lateral streaks. 
The pupa is smaller and much more slender, but is coloured like that 
of P. memnon. The imago emerges in from 14 to 15 days. Rothschild 
records this species from Sumatra as (e), P. helenus palawanicus , 
Staudinger. 
582. Papilio ( Charus) iswara, White. 
Hagen. Very rare in our area, more common on the western 
boundary, as most of the specimens received have been from the 
Gayoe-lands. Occasionally taken at Selesseh and Besitan. Found 
in the plains and outer hills. During a short collecting trip in Indra- 
giri in the middle of Sumatra, Dr. Friedl Martin found this species very 
plentifully in February, 1895, but not a single specimen of P. helenus , 
Linnaeus, was observed. 
583. Papilio ( Charus ) nephelus, Boisduval. 
Grose Smith. Hagen as albolineatus, Fabricius [sic] ; nephelus ; and 
nephelus , var. saturnus. Wallace. Staudinger. Distant as nephelus , 
var. saturnus. Forbes as saturnus . Butler as saturnus. Distant notes 
that in a Sumatran specimen of this species in his collection “ The 
pale stramineous markings above are more or less shaded with dark 
ocliraceous.” This remark probably applies to a female. P. albolineatus , 
Forbes, was described from Borneo, and is figured in Aid, vol. ii, pi. 
clxvi, fig. 1. We have seen no specimen of it from Sumatra, though 
Dr. Hagen has recorded it from thence. P. nephelus is rarer than 
P. helenus, Linnaeus, and occurs throughout the year in the plains and 
on the outer hills, but not on the Central Plateau. It is also a true 
forest butterfly ; the males have a very quick and restless flight, are 
fond of flowers, but settle only for a very brief period; never observed 
