Comparatively few of the native summer flowers of America will bloom along roads and in vacant lots, in waste places and dumps and edges of fields. It is, oddly enough, the plants brought over accidentally from Europe and Asia which are the flowers known most familiarly as summer blossoms around towns and habitations. Among them is butter-and-eggs, Linaria, the wild yellow toadflax.
Linacia vulgaris Hill.
June - October Roadsides, sands.
It might just as well be a native flower; it is elegant enough to belong among American flora. It is closely related to snapdragons and plainly shows the family resemblance in the complicated flower with its snap-shut mouth. The butter and eggs flower is constructed so that no insect may get inside unless it is heavy enough and strong enough to force open the flower. The weight of a bee on the bright, orange-yellow padded lip will force it open. The bee dives head-first inside to get the nectar which has been kept sale from rain and marauding insects, and at the same time the bee with its bind feet holds open the lip of the flower.
The flower is pale yellow, the lip bright orange - color and shape so much like that of an egg yolk thai the common name of butter-and-eggs long ago was given to it. Ernest Thompson Seton, the naturalist, tells a story of a little yellow dragon which died when a fried egg - always death to dragons - became stuck in its throat, and he was transformed into the butter-and-eggs plant.
The leaves and stem of this plant are smooth and thin, pale grey-green. It grows in waste places and sandy soil over much of the eastern part of the continent and is commonly found in Illinois.