OF ORNAMENTAL EXOTIC PLANTS. 
205 
CHAPTER XLIX. 
ACANTHACEtE R. Brown. 
Essential Character. — Calyx usually five-parted and very much 
imbricated, persistent. Corolla monopetalous, hj-pogynous, bearing the 
stamens, generally irregular ; the limb ringent or two- lipped, but 
sometimes one-lipped or nearly equal, deciduous. Stamens mostly 
two, both bearing anthers, sometimes four, didynamous, the shorter 
ones being sometimes sterile. Anthers one or two-celled, generally 
opening lengthwise. Ovary seated in a disk, two-celled; the cells 
either two or many-seeded. Placentae parietal, though adhering in the 
axis. Style one. Stigma two-lobed, rarely undivided. Capsule two- 
celled, bursting elastically with two valves. Seeds roundish, hanging 
by the ascending processes of the placenta. Testa loose. Albumen 
none. Cotyledons large, ronndish. 
Description, &c. — Most of the plants belonging to this order are natives of the tropics, and most of them have 
very ornamental flowers. Very few can be said to belong to the greenhouse, but those which do are extremely 
ornamental. Some of the species that are properly stove plants may be grown in the open air by treating them as 
annuals, and raising them from seed every year on a hotbed. Thus, though most of the plants included in the 
order are natives of hot climates, singularly enough the one from which the order takes its name is perfectly hardy 
in Great Britain. 
GENUS I. 
RUELLIA Un. THE RUELLIA. 
LiM. Syst. DIDYNAMIA ANGIOSPERMIA. 
Generic Character. — Calyx five-cleft, equal. Corolla funnel- | Capsule many-seeded, splitting across the cells into two valves, each 
shaped ; limb five cleft, nearly equal, spreading. Anthers two-celled. | bearing a portion of the dissepiment across the centre. 
Description, &c. — Nearly all the species of this genus are stove plants, but two of them may be kept in a 
greenhouse provided they have a little heat by plunging the pots in a hot-bed, or giving them bottom-heat in some 
other way, just when the plants are forming their flower buds. The name of Ruellia was given to this genus in 
honour of Dr. Ruelle, a French botanist. 
1.— RUELLIA CILIATIFLORA Hook. THE FRINGE-FLOWERED RUELLIA. 
Engravings. — Bot. Mag., t. 3718 ; and ova fig. 1, in PI. 42. 
Specific Character. — Herbaceous. Leaves petiolate, ovate, un- 
equally serrated, covered with a hairy pubescence. Panicles terminal. 
leafless. Calyx in unequal lobes; segments subulate. Tube of the 
corolla angularly curved ; limb oblique, lobes undulated, sub-rotund, 
dentately ciliated. 
Description, &c. — This very beautiful plant was brought by Mr. Tweedie from Buenos Ayres in 1839, and 
it produces its beautifully fringed and delicate lilac flowers in September. It is truly herbaceous, growing about 
a foot and a half high, and it has very handsome foliage. 
OTHER SPECIES OF RUELLIA. 
R. AUSTRALIS Cav. 
This species is a native of New Holland, where it has been found in the neighbourhood of Port Jackson. It 
seems, however, to have a very widely extended botanical range, as it has also been found in several parts of the 
East Indies. It has small dark-hlue flowers. It was introduced in 1820. 
