1895.] L. de Niceville & Dr. L. Martin— Butterflies of Sumatra. 379 
form of one and the same species ; the latter is not found in Sumatra, 
itf. lalassis is confined to Gilolo and Amboina according to Mr. Moore. 
Not uncommon in the plains, hut occurs less frequently than M. mineus , 
Linnaeus, and M. horsfieldii , Moore. 
53. *Mycalesis ( Calysisme ) polydecta, Cramer. 
Snellen as justina. Butler. Mr. Moore gives the c ‘ Papilio” justina, 
Cramer, which was described from the Coromandel Coast of South 
India, as a synonym of M. polydecta , and restricts the species to Eastern, 
Central, and Southern India, and Ceylon. As the figure of M. justina 
is very similar to the wet-season form of M. mineus , Linnaeus, while the 
figure of M. polydecta reminds one at once of the recently-described 
M. horsfleldii , Moore, it is, I think, probable that Messrs. Snellen and 
Butler have incorrectly recorded this species from Sumatra. Dr. Hagen 
gives M. justina as a synonym of M. mineus. 
54. Mycalesis ( Calysisme ) mineus, Linnaeus. 
Hewitson. Grose Smith as ostrea. Hagen as drusia , and as mineus , 
Butler [sic.]. Distant. Mr. Moore considers that both M. milieus and 
M. drusia , Cramer, represent the wet-season form of one and the same 
species. No dry-season form of it (M. otrea , Cramer, nec M. ostrea , 
Westwood, which also equals the dry-season form of M. mineus ), occurs 
in Sumatra. It is the commonest species of Mycalesis found in the island, 
and flies everywhere with M. medus , Fabricius, where there is grass 
and a little jungle for it to retire into. 
55. Mycalesis ( Calysisme ) horsfieldii, Moore. 
Calysisme horsfieldii, Moore, Lep. Ind., vol. i, p. 197, pi. Ixvi, figs. 2, 2a, 2b, male, 
xcet-season form ; 2c, dry-season form (1892). 
The dry- and wet-season forms of this species differ but little. I 
have specimens also from Nias Island and Java. M. mineus , Linnseus, 
M. perseus , Fabricius, and M. horsfieldii all occur at the same time and 
place, so there can be no question of one being perhaps a seasonal form of 
the other. Besides, the “ male-marks ” of the three species differ con¬ 
siderably, that of the latter on the upperside of the hindwing being very 
much larger than those of the other two species. Dr. Martin has bred this 
species as well as M. mineus , M . janardana, Moore, and M. anapita , Moore, 
from eggs laid by confined females ; the larval stage of all four being 
very similar and not easy to be differentiated, if mixed together. M. hors¬ 
fieldii and M. anapita would not eat the common ubiquitous Gramine&e , 
so he had to give them other and rarer kinds of grass.' M. horsfieldii is 
common in the plains of Sumatra, the female rarer than the male. 
J. ii. 48 
