butter-and-eggs, (Linaria vulgaris), perennial herbaceous plant of the Plantaginaceae family, native to Eurasia. The plant is widely naturalized in North America, where it is considered an invasive species.
Butter-and-eggs grows up to 1 metre (3.3 feet) tall, bears narrow flax-like leaves, and produces showy yellow and orange flowers that are two-lipped and spurred like snapdragons. Seeds are borne in a capsule fruit and feature a small notched wing for wind dispersal.