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LEPID OPTEDA INDIO A. 
between the two broods of wet-season butterflies (May—June and August—Septem¬ 
ber), I have never observed any difference. But between specimens of tbe wet and 
dry-season broods there are in many genera very perceptible differences. There is a 
difference in size, the wet-season specimens being generally smaller, and there are 
minor differences in the angulation of the wings and in the tone and purity of the 
colouring below. But the most remarkable difference is in the presence of large eye¬ 
like spots on the underside of the wet-season forms, either absent or greatly reduced 
in those of the dry season. To give an example, the Sarju Valley was on September 
20th full of ragged specimens of a strong-ocellated butterfly ( Mycalesis mineus proper), 
which a week later was succeeded by swarms of a larger, more angulate, non-ocellate 
insect ( Myc. visala), precisely similar in its structure, and especially in those very 
complex organs, the prehensores, which in general mark by strong differences the 
slightest specific variations. In the same way Melanitis Leda was succeeded by the 
non-ocellate Mel. Ismene, and Junonia Asterie by the non-ocellate .7. Almana. Such 
facts are best studied in countries where the wet and dry seasons are well marked, 
and there is none better than Travancore, where in 1882-3 I first observed these 
curious metamorphoses. Hitherto I have only found them to exist in Junonia, 
Yphthima, Melanitis, and in the following groups of Mycalesis — Galysisme, Orsotriama, 
Telinga, Gareris, Virapa, and Samanta. Many genera of the Satyridae seem to pro¬ 
duce onlv the two wet-season broods, and so fail to show what variations the weather 
would produce in their markings. Again, some dry countries produce only the dry 
forms, and some wet countries only the wet forms. For instance, I believe that 
Sindh produces only the dry-weather form Junonia Almana, while the wet climate of 
Ceylon and Singapore produces only J. Asterie. In dry Orissa, the wet and dry 
forms of Orsotriaena Medus and 0. Runeka are tolerably distinct, and the latter is 
the commoner of the two. But on the damp Malabar Coast, of the representative 
forms Orsotriama mandata and 0. mandosa, the latter, the dry-weather one, is scarce 
and imperfectly differentiated. The cause of this seasonal dimorphism would be a 
curious subject of study, but I have no suggestions to offer myself. Mr. de Viccville 
has recently observed to me that perhaps, owing to the rank vegetation of the rainy 
season, the butterflies are better concealed, and have therefore been free to assume 
these handsome spots, under the influence, perhaps, of sexual selection. This view 
is, I think, somewhat strengthened by certain facts. The dry season forms are all 
more or less leaf-like in shape and colouring, while in the wet-season ones there is no 
such mimicry. This argues greater exposure to danger in the dry season. Remem¬ 
bering, however, the remarks of Darwin and Wallace on the protective nature of the 
ocelli of birds, borne out by the testimony of all sportsmen, and observed by me in 
the case of the common wild Peacock, I am inclined to think that the ocelli are a 
direct protection to the insect during the rains. Certainly that is likely to be the 
