The Ides of May
I looked into the name of D. ida-maia a few years ago, and read somewhere that it was named after a lady named Ida Mae. But I was never totally satisfied with this explanation, because it always blooms on May 15, which is the Ides of May, a date newly significant to me. So with the help of the internets, I tracked down Alphonso Wood's original 1867 description of what he called Brevoortia ida-maia:
This plant was first noticed by Mr. Burke, stage-driver, in his daily route, and by him my own attention was first called to it. He had given it the name of "Ida May, in affection for his little daughter,"—a name quite appropriate, moreover, as on the Ides (i.e., the 15th) of May, the plant begins to flower.
The type locality was on the stage road from Shasta City to Yreka.