Proustia krugiana Urb.

• Title

  Proustia krugiana Urb.

• Author(s)

  Nathaniel Lord Britton, Frances W. Horne

• Scientific Name

  Proustia krugiana Urb.

• Description

  Flora Borinqueña Proustia Krugiana Consul Krug's Proustia Family Carduaceae Thistle Family Proustia Krugiana Urban, Symbolae Antillanae 1: 471. 1899. An endemic shrub of Porto Rico, restricted to relatively dry banks, woodlands, and thickets in the southern and southwestern districts, ascending to about 600 meters elevation on the southern mountain slopes, local in distribution, but plentiful in some places; the very strong fragrance of its bright yellow flowers draws attention to its proximity, when in bloom. The species was named in honor of Carl Wilhelm Leopold Krug, former German consul at Mayaguez, a diligent student of plants, and is the only one of its genus inhabiting Porto Rico, the nearest relatives being Proustia crassinervis and Proustia stenophylla of Haiti. Neither Spanish nor English popular names have been recorded. Proustia, established by the Spanish botanist Lagasca in 1811, named in honor of a Spanish chemist Proust, consists of about 10 species of shrubs and woody vines, natives of tropical America, the typical one, Proustia pyrifolia, native of Chile. Their leaves are alternate, toothed, pinnately veined, their small heads of flowers clustered; the involucre of the few-flowered heads is cylindric, its small bracts in several series, the outer much shorter than the inner; the corollas are somewhat 2-lipped, this genus being classified in the tribe Mutisieae, characterized by this feature, with numerous genera and species in South America, but few in the West Indies; the stamens have arrow-shaped anthers. The minute fruits (achenes) are ribbed, and bear numerous soft, capillary bristles. Proustia Krugiana is a vine-like shrub, often 3 or 4 meters long, with slender, round branches and hairy, young twigs. The very short-stalked, or stalkless leaves are stiff, firm in texture, pointed, usually slightly toothed, but sometimes without teeth, from 2 to 9 centimeters long, the upper surface rough, the base rounded, or somewhat heart-shaped. The flower-heads are in several or many, small clusters, subtended by small leaves; the involucres are about 8 millimeters long, about 7-flowered, their bracts hairy, the inner ones narrower and longer than the outer; the limb of the bright yellow corolla is about 3 millimeters long. The slender achenes are about 6 millimeters long, the pappus straw-colored. Our illustration was first published in Addisonia, plate 500, September, 1930.