HYDROPHYLLACEAE

the waterleaf family, which contains about 18 genera and at least 250 species of plants richly represented in western North America and widespread in tropical and temperate areas. It is best-known for a few garden annuals. Most are herbs, but the family also contains a few shrubs. The species have alternate, often hairy leaves, regular flowers with five-lobed corollas (united petals) cut to the middle of the blossom, and a one- or two-celled ovary. Hydrolea spinosa, one of a genus of about 20 tropical herbs, is a perennial that grows to 1 m (3.5 feet) tall, with sticky, hairy, oval leaves and wheel-shaped, blue flowers 1.3 cm (0.5 inch) across. It is native in the American tropics, as is the shrub Wigandia caracasana. Wigandia, growing to 3 m (10 feet) tall, bears stinging hairs on its large, oval leaves and produces spikelike clusters of blue flowers. The Virginia waterleaf (Hydrophyllum virginianum) has pale-violet or white flowers and may grow to 1 m tall.