Barleria prionitis L.

• Title

  Barleria prionitis L.

• Author(s)

  Nathaniel Lord Britton, Frances W. Horne

• Scientific Name

  Barleria prionitis L.

• Description

  Flora Borinqueña Barleria Prionitis Prionitis Family Acanthaceae Acanthus Family Barleria Prionitis Linnaeus, Species Plantarum 636. 1753. The functions of spines and of prickles in the physiology of plants are, probably, related in some way to their transpiration of water. A more obvious explanation of their presence would be that of serving as a defense against predatory animals, including man, as in some cases they doubtless do, but that they originated for such purpose seems very doubtful. An even simpler, but improbable answer to the question is that they are vestigial organs, of no use to the plant. The topic is the more complicated because in related species of the same genus, some are spiny, some quite spineless, a condition obtaining in Barleria, where we find at least 100 species of shrubs and herbs. They are mostly natives of the Old World, but several have been introduced into the American tropics, either as garden flowering plants, or as weeds. The generic name commemorates the French botanist Jacques Barrelier, who lived from 1634 to 1673. These plants have opposite leaves, without teeth. Their flowers are variously clustered, commonly in terminal, bracted spikes, yellow in the kinds found in Porto Rico; the calyx is deeply 4-cleft, with 2 of the segments larger then the other 2; the corolla has a tube about as long, or longer than the spreading, 5-lobed limb; the 4 stamens are borne on the corolla-tube in 2, unequal pairs; the pistil has a 2-celled ovary with 2 ovules in each cavity, a long style and a blunt stigma. The fruit is a small, usually oblong capsule, containing 1 or 2 flat, broad seeds. Barleria Prionitis is a shrubby plant, native of tropical Asia and Africa, about a meter high, or lower, armed at the leaf -axils with needle-like, yellowish spines about 2 centimeters long; it is grown in gardens for its attractive, yellow flowers, and occasionally escapes to roadsides or waste grounds. The oblong or elliptic, thin leaves are stalked, narrowed to both ends, and from 3 to 9 centimeters long; the stalkless flowers are borne in the leaf-axils, or form terminal bracted clusters, their bracts pungently pointed, from 1.5 to 2 centimeters long; the calyx is from 12 to 15 millimeters long, the corolla 3 or 4 centimeters long, the pointed capsule about 2 centimeters long. Our illustration was first published in Addisonia, plate 329, June, 1925.