The New Student's Reference Work/Zygomorphous Flowers

Zygomorphous (zǐgő'-môr'fǔs) Flowers, those in which the parts of a single set are not all alike. The term is chiefly applied to irregularity of petals. For example, in the sweet pea the petals are very much unlike. In most of the mints the five petals are so, modified that two form an upper lip and three a lower lip, making the so-called bilabiate flower. The contrasting term is actinomorphic flowers. See.