370 



HENDERSON'S HANDBOOK OF PLANTS 



EHI 



feet, and gained a position considerably in 

 advance of their parent trunlis. After this, 

 fewer additions are made to tlie roots, but 

 the head begins to expand in every direction, 

 spreading its branches on all sides. These 

 branches, in their turn, send dowalong, slen- 

 der roots, like those of the Banyan Tree 

 (Ficus Indica), which, rapidly elongating, de- 

 scend from all heights, and reaching the 

 water, penetrate the mud, becoming in time, 

 independent trees. Thus a complicated laby- 

 rinth is at length formed." The fruit of the 

 species is edible, and its fermented juice is 

 made into a light wine. In Borneo a coarse, 

 bitter salt is extracted from their aerial roots. 



Rhizophora'ceae. A natural order of tropical 

 trees or shrubs, with opposite, entire leaves 

 and axillary flowers, closely allied to Combre- 

 tacecB and Lythraceoe. The order contains 

 about fourteen genera, the chief of which are 

 Halopetalum and Rhizophora. 



Rhoda'nthe. From rhodon, a rose, and anthos, 

 a flower ; in allusion to the color of the tiower- 

 heads. Nat. Ord. CompositcB. 



A very beautiful genus of half-hardy an- 

 nuals found in western Australia. R. Man- 

 glesii and its varieties have white, rose, crim- 

 son, and purple flowers. These plants are 

 admirably adapted for the border in summer, 

 or the conservatory or green-house in winter, 

 as they come into flower early, and continue 

 for a long time. The flowers, if gathered 

 when 3'oung and dried in the shade, will re- 

 tain their beauty during the winter, making 

 them valuable for bouquets of dried flowers. 

 For perfection of growth in the border, the 

 seed should be sown in March in the green- 

 house or a hot-bed, and carefully grown on in 

 small pots until all danger from frosts is past, 

 ■when they may be turned out into the open 

 border. For winter flowering the seed should 

 be sown in August or September, Introduced 

 by Capt. Mangles in 1832, 



Rho'dea. See Rohdea. 



Rhodio'la. From rhodon, a rose. Nat. Ord. 

 Crassulacece. 



A genus of succulent plants, separated from 

 Sedum, on account of their bearing fertile and 

 barren flowers on distinct plants. 



Rhodochi'ton. A genus of ScrophulariacecB, 

 differing but little from LophcHpertnum, the 

 calyx being less divided and the corolla not 

 so open. 



R. volubile, is an interesting and useful 

 climber either for the green-house or for sum- 

 mer decoration in the flower-garden. It can 

 be increased by cuttings or seeds. Introduced 

 from Mexico in 1833. 



Rhodode'ndron. Eose Bay. From rhodon, a 

 rose, and dendron, a tree. Nat. Ord. Ericaceae. 

 A genus of well-known evergreen shrubs 

 and low-growing trees, remarkable for their 

 beautiful flowers and thick, luxuriant, glossy 

 foliage. The species are widely diffused, be- 

 ing indigenous to the United States, Europe, 

 Asia, and the Indies. Some of the species are 

 perfectly hardj', and others require the pro- 

 tection of the green-house. Of our native 

 species R. maximum (Great Laurel), common 

 from Maine to Ohio, is a tall-growing shrub, 

 with leaves from four to ten inches long, very 

 thick and glossy. The flowers are a light 

 rose color, nearly white, with greenish throat, 



RHO 



and spotted with yellow or light red. R. 

 Catawbiense, common on the AUeghanies from 

 Pennsylvania southward, is perfectly hardy, 

 and flowers most profusely. It seldom grows 

 above four feet high, but forms a symmetri- 

 cal shrub, exceedingly ornamental for a lawn 

 plant. This species is the parent of all our 

 hardy varieties, having been hybridized with 

 the Nepal species, R. arboreum. From this 

 cross there has been raised a great number of 

 beautiful kinds, most of which are hardy in 

 the latitude of New York. The varieties in- 

 clude colors from nearly pure white to dark 

 crimson. All the hardy sorts are of easy cul- 

 ture, growing freely in almost any loamy soil, 

 but they prefer a moist situation, protected 

 from cold winter winds. When first planted 

 they should be mulched with any convenient 

 material that will prevent evaporation and 

 keep the roots moist and cool. Several fine 

 species have been introduced from the Hima- 

 layas, a few of them bearing but little resem- 

 blance to the common Rhododendron, one be- 

 ing a climber. The plants are propagated by 

 seeds, cuttings, laj-ers, or by grafting. Azalea, 

 and Rhodora, are included in this genus by 

 Benthara and Hooker. 



Rhodole'ia. From rhodon, a rose ; alluding to 

 the color of the flowers. Nat. Ord. Hamameli- 

 dacecB. 



R. Championi is a beautiful green-house 

 shrub, rivalling the Camellia, but of a very 

 curious structure. It forms a small, ever- 

 green tree, but would probably blossom freely 

 as a shrub. The leaves are alternate, elliptic- 

 ovate, bright green above, glaucous beneath. 

 The flower-heads grow at the ends of the 

 branches, and are two inches and a half in 

 diameter, of a beautiful rose color, enclosing 

 a large number of stamens. These heads 

 usually consist of five flowers. It is a native 

 of China, growing in the woods about Hong 

 Kong. Introduced in 1850. 



Rhodomy'rtus. From rhodon, a rose, and 

 myrtos, myrtle ; in allusion to the rose-colored 

 flowers, and its alliance to the Myrtle. 



A genus of Myrtacece, containing a few spe- 

 cies of trees or shrubs, natives of Eastern 

 Australia, tropical Asia, and the Indian Archi- 

 pelago. R. tomentosa, the only cultivated 

 species, known as the Hill Gooseberry, and 

 Indian Hill Guava, has ovate-velvety leaves, 

 downy beneath, and beautiful rose-colored 

 flowers. Introduced from China in 1776, under 

 the name of Myrtus tomentosa. 



Rhodo'ra. From rhodon, a rose ; alluding to 

 the color of the showy flowers. Nat. Ord. 

 Ericacem. 



R. Canadensis, the only species, is a hand- 

 some, low-growing shrub, with oblong, de- 

 ciduous leaves, whitish and downy under- 

 neath ; the showy, rose-purple, rarely white 

 flowers appearing rather earlier than the 

 leaves. It is a native of cold woods and 

 swamps, New England to Pennsylvania, and 

 northward on the mountains. Included by 

 Bentham and Hooker under Rhododendron. 



Rhodotha'mnus. From rhodon, a rose, and 

 thamnos, a shoot or branch. Nat. Ord. Eri- 

 cacecB. 



This genus consists of a solitary species, 

 found in the Alps of Europe, and long known 

 as Rhododendron Chamceciatiis. It is a pretty, 

 dwarf, almost prostrate, evergreen shrub, 



