82 LEPIDOPTERA INDICA. 



I landed in Ceylon, October 25tb, 1S95, and I certainly tliouglit that I had stepped 

 into a land of butterflies. The harbour, streets, and large promenade, the Galle 

 Face of the seashore, was alive with butterflies, and, being mostly composed of 

 Catopsilias, looked like a snow-storm. In order to gain some idea of their numbers, 



1 selected two points, one at the edge of the sea and the other twenty yards fi'om 

 it, and then counted them as they flew past. The result of my calculation, and that 

 of ray companion, taken separately, gave 14,000 insects between 10 a.m. and 



2 p.m. The flight usually lasts about a week ; we have therefore 98,000 butterflies 

 passing through a space sixty feet broad in twenty-eight hours. In round 



numbers 100,000 The butterflies, in whatever part of the island they 



happen to be hatched, inamediately begin to migrate, so that on the same day the 

 migration is as vigorous in one part of the island as in another. As the butterflies 

 hatch in Colombo they immediately fly north, and their places are promptly filled by 

 the insects coming up from Galle, the Galle ones by those from Hambantotte, and 

 so on, round to Trincomalee, beyond which, in the uninhabited country to the north, 

 I have been unable to trace them. The proof that the insects on the Trincomalee 

 side really do follow the coast, and come to Colombo, is shown by the fact that it 

 is only during the flights that certain buttei'flies, otherwise confined to that portion 

 of the island, Papilio Jason, for instance, occur at Colombo, and are there seen 

 migrating in the same frantic haste as their companions. On one occasion, on 

 December 2nd, i.e. in the wet-season, I was observing the flight from Tort Frederick, 

 Trincomalee. The butterflies came from the northern shore straight across the sea 

 to the end of the peninsula on which Fort Frederick is built ; several bushes of the 

 food-plant of GalojosiUa Pyranthe wei'e growing there, and these were literally 

 covered with eggs, as many as half a dozen on a single leaf ; the bushes were so 

 speckled with the multitude of eggs that they looked as if handfuls of sago had 

 been scattered over them. The flights in November and December on both sides of 

 the island undoubtedly comprise a majority of females, but scarcely a single larva 

 out of this multitude of eggs could possibly have come to maturity ; there was not 

 enough food for half of them, and on a previous migration the bushes not far oS" 

 were completely stripped by the larvsB. The insects comprising the coast flight are 

 almost entirely Catojysilias, two species of Appias, Euplcea Asela and Montana, in 

 the Hill districts, and Danais septentrionis irregularly. I should have mentioned 

 that the process of laying eggs was totally contrary to what one usually observes — 

 there was no attempt to choose a suitable leaf, no deliberation displayed about the 

 operation at all, but every female seemed possessed with the one idea of getting 

 rid of her eggs with the utmost expedition, utterly regardless of the fate 

 of the future larvce, and then madly continuing her flight. When in full 

 migration they fly with great rapidity, and can give points to Colias edusa. 



