Ultraviolet reflectance properties of flowers in 26 East Mediterranean wild species and three cultivated species of the Cruciferae are surveyed. These properties were disclosed by photography of fresh or herbarium specimens through a visible‐light absorbin filter. The so‐revealed spectral polymorphism is related to the previously known visible flower colors. Ultraviolet floral patterns which act as nectar guides to pollinators are described. Hitherto unreported patterns were found to result from ultraviolet absorption by sepals, ultraviolet reflection from anther tips, and, in one case, ultraviolet absorption by a peripheral part of the corolla. In some cases patterns differ between closely related taxa and could therefore be of diagnostic value.

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