A little later, when I enthusiastically reported it to a professional lepidopterist he brushed it aside. "A common occurrence the world over, Rhopalocera gathered in damp places to drink." I, too, had observed apparently similar phenomena along icy streams in Sikkim, and around muddy buffalo-wallows in steaming Malay jungles. And I can recall many years ago, leaning far out of a New England buggy to watch clouds of little sulphurs flutter up from puddles beneath the creaking wheels.
The very fact that butterflies chose to drink in company is of intense interest, and to be envied as well by us humans who are temporarily denied that privilege. But in the Bay of Butterflies they were not drinking, nor during the several days when I watched them. One of the chosen patches of sand was close to the tide when I first saw them, and damp enough to appease the thirst of any butterfly. The other two were upon sand, parched by hours of direct tropical sun, and here the two layers were massed.
The insects alighted, facing in any direction, but veered at once, heading upbreeze. Along the riverside of markets of tropical cities I have seen fleets of fishing boats crowded close together, their gay sails drying, while great ebony Neptunes brought ashore baskets of angel fish. This came to mind as I watched my flotillas of butterflies.
I leaned forward until my face was hardly a foot from the outliers, and these I learned to know as individuals. One sulphur had lost a bit of hind wing, and three times he flew away and returned to the same spot. Like most cripples, he was unamiable, and resented a close approach, pushing at the trespasser with a foreleg in a most unbutterfly-like way. Although I watched closely, I did not see a single tongue uncoiled for drinking. Only when a dense group became uneasy and pushed one another about were the tongue springs slightly loosened. Even the nervous antennæ were quiet after the insects had settled. They seemed to have achieved a Rhopaloceran Nirvana, content to rest motionless until caught up in the temporary whirlwinds of restlessness which now and then possessed them.
They came from all directions, swirling over the rocks, twisting through nearby brambles, and settling without a moment's hesitation. It was as though they had all been here many times before, a rendezvous which brooked not an instant's delay. From time to time some mass spirit troubled them, and, as one butterfly, the whole company took to wing. Close as they were when resting, they fairly buffeted one another in mid-air. Their wings, striking one another and my camera and face, made a strange little rustling, crisp and crackling whispers of sounds. As if a pile of Northern autumn leaves, fallen to earth, suddenly remembered days of greenness and humming bees, and strove to raise themselves again to the bare branches overhead.