
In fifth and sixth grade, we had a French teacher who was known simply as Mademoiselle. She was from France and every once in a while, told us about the country, a little tidbit or two, nothing major.
It would seem, according to Mademoiselle, that the first of May, le premier Mai, was celebrated by the giving and receiving of lilies of the valley.
I think Mademoiselle was never in Boulder CO on le premier Mai.