We had a killing frost only a night or two ago, the thermometer in sheltered positions marking twenty-five to twenty-eight degrees. It withered the grape leaves and took all tender things of the gardens and fields. Such a temperature for a long autumn night one would think would be death to those frail creatures of summer,--the butterflies. Yet to-day I saw a monarch soaring on strong red wings about the top of a great pine tree, sixty feet in air, seemingly seeking food among the resinous tips.
Across the fields a sulphur flitted his dainty way like a yellow fleck of animated sunshine. A few grizzled goldenrod and frost-bitten asters still bloom feebly for him, but in the swamp, undismayed, the witch-hazel twists its soft, yellow petal-fingers and sends out dainty perfume for his delectation. Over at the clubhouse a hunter’s butterfly and two well-preserved specimens of the painted lady sunned themselves in warm spots on the shingles.
In spite of the summerlike quality of the day these seemed anxious. Now and then they fluttered eagerly about the building trying window fastenings and poking their heads into cracks, seemingly trying desperately to get in. They tried on the shady sides of the building as well as on the sunny, and though I cannot prove that it was not mere aimless wandering, it seemed to me to be done with a definite design. I think the painted ladies were hunting shelter in expectation that the day was a weather breeder. I think they knew that more cold weather was sure to follow, and though they had found shelter in which they were able to weather the first cold snap, they feared lest the next be too much for them, and hoped to get inside in some crevice next to a stove funnel.
Some butterflies, notably the _Antiopa vanessa_, which appears sometimes on warm days in February, winter successfully. Probably the _vanessa_ is particularly resistant to cold. Probably also he has a peculiar faculty for finding shelter and safety, and I think the two hardy examples of _Pyrameis cardui_ showed signs of some of the same instinct.
Later, in the full heat of the afternoon, when the thermometer stood at eighty degrees, I stood by the side of a long, straight country road leading north and south. One monarch butterfly after another was soaring along this road, seemingly not in haste, but making, nevertheless, a speed of six or seven miles an hour. And every one of them was heading due south on the trail of the one ahead, as if in a game of follow-your-leader. Was the leader a wise old butterfly who had made the long southern road before, and were these others monarchs of this year’s growth following him that they might reach the goal in safety?