4. Browallia Linnaeus, Sp. Pl. 2: 631. 1753; Gen. Pl. ed. 5, 278. 1754.
[For John Browall, 1707–1755, Bishop of Åbo, Sweden, and friend of Linnaeus]
Philip D. Jenkins†
Herbs, annual or perennial, or shrubs, taprooted or with fibrous roots, hairs simple or with multicellular glandular heads. Stems erect to decumbent and sprawling, branched. Leaves alternate, petiolate or sessile; blade simple, margins entire. Inflorescences axillary and terminal, solitary flowers or racemoid. Flowers 5-merous, bilaterally symmetric; calyx accrescent, tubular-campanulate, lobes 5, triangular, as long as or slightly longer than capsule, not inflated; corolla white, creamy white to yellowish, blue, or violet, bilateral (sometimes appearing 4-parted by fusion of abaxial 2 lobes), salverform, lobes spreading or reflexed, rounded; stamens 4, unequal, (abaxial 2 with 2 fertile thecae each, adaxial 2 with 1 fertile and 1 abortive theca each), sometimes also with 5th smaller stamen, abaxial 2 inserted in distal 1/2 of corolla tube, adaxial 2 at mouth of corolla; anthers basifixed, spheric or subspheric, dehiscing by longitudinal slits; ovary 2-carpellate; style proximally slender, distally sigmoidally curved and broadened, (wrinkled); stigma capitate-bilobed. Fruits capsules, ovoid, (2-valved). Seeds (4–50), prismatic or concave abaxially and convex adaxially. x = 10, 11.
Species 5 (2 in the flora): Arizona, Mexico, Central America, South America, introduced in Asia, Africa, Indian Ocean Islands, Pacific Islands, Australia.
J. F. Macbride (1962) commented on the difficulty of circumscribing morphological species in Browallia, leading him to question the genetic status and taxonomy of species in the genus. He noted that the annuals, especially, had weedy tendencies whose considerable morphological diversity appeared to be influenced by environmental conditions. Plants of some species grown in the garden from wild-collected seed exhibit characteristics found in the widely cultivated B. americana after a single generation.
