Leaves opposite; calyx 4-5-lobed; sepals 5; petals 5, united, sometimes 2-lipped; stamens on tube, 2 or 4 in 2 pairs; fruit a capsule, often club-shaped, opening elastically.
Flame Acanthus (Anisacanthus wrightii) is covered with scarlet flowers from early summer until frost. It is a low, widely branched shrub, about 2 feet high, found in rocky soil of the mountains of West Texas. The corollas have a narrow tube and five narrow, spreading lobes which are nearly equal but somewhat 2-lipped. The two stamens and the style extend beyond the corolla. The small leaves are ovate-lanceolate in shape and are 1-2 inches long.
The flame acanthus is an excellent garden shrub for dry regions and has been known in cultivation for some time. This species is named in honor of Charles Wright, an early collector of Texas plants and one of the first teachers in the state. Wright was a Yale graduate who collected plants in Texas from 1837 to 1852 for Dr. Asa Gray of Harvard University. He accompanied a baggage train to El Paso in 1849, and in 1851 he joined the Graham Boundary Survey. On both of these trips he collected many plants not previously known to science.
WILD PETUNIA
Wild Petunia. Ruellia (Ruellia nudiflora) has flowers very much like those of the cultivated petunia, a member of the potato family. It is a very common plant in Central and South Texas, growing in open woods or on rich prairies. It frequently takes possession of lawns and flower beds.
The plants are erect, 12-16 inches high, and have few branches. The few leaves are oval, narrowed at the base, wavy-margined, and blunt or rounded at the apex. The forking flower clusters have one to five flowers open at the same time. The flowers do not last very long. Leaves and stem are often marked with red or purple.
The delicate, funnel-shaped corollas have five spreading lobes and are about two inches long. The four stamens are inclosed in the tube. The seed-capsules are nearly an inch long and turn brown as they mature.
This ruellia was formerly confused with Ruellia tuberosa, a tropical plant with tuberous roots. The ruellias belong to a large group of plants with about 200 species most of which are found in tropical South America. They are named for Jean de la Ruelle, an early French physician and botanist.
There are several other ruellias widely distributed in the wooded sections of the state. The hairy ruellia (Ruellia ciliosa) is abundant on the prairies in Texas and the Eastern States. Miss Eaton, in an article in the National Geographic in 1925, reports that carpenter-bees use circular pieces of the corolla to plug off their nesting cells made in tunnels in soft wood. Drummond’s ruellia (Ruellia drummondiana) is found in woods in Central Texas. The flowers are rather small and are nearly hidden by the leaves.