The Butterfly's Nose Knows

Two of MLH's lilies, Turks-cap and Montreux, represent a high level of lily development. The larger purple cluster also adds a thick, spicy aroma to the garden and house, a look and smell that announces its nectar to the world, or so one might think.
Last evening, while sipping an AB on the cottage's small porch entry, I watched a yellow swallowtail butterfly, flutter-bying among these lilies. It landed on the purple ones, briefly, then transferred its attention to the Turk's-cap. Over some 20 absorbing minutes, it probed and probed each orange blossom in turn, flitting but momentarily onto a purple blossom, only to return to the orange.
I am an apparent dilettante when I try to guess by looks and size and scent what lily blossom an expert nectar sipper might prefer. In future, I'll leave such fundamental affairs to the experts.