AND GENEKAL HORTICULTURE. 



371 



RHO 



with small oblong leaves, toothed and fringed 

 on the margin, and solitary pale purple flow- 

 ers, produced in May or June. 



Rhodoty'pus. From rhodon, a rose, and typos, 

 type. Nat. Ord. Rosacece. 



R. kerrioides, the only species at present 

 known, is a slender-branching, hardy, ever- 

 green shrub, remarkable for its large, termi- 

 nal, pure white flowers, resembling those of 

 an Althaea, but smaller. It is well adapted for 

 the lawn, contrasting finely with the Wei- 

 gelia and other hardy ornamental shrubs. 

 Introduced from Japan in 1886. Increased 

 readily by cuttings or layers. 



Rhoeo discolor. This is given in "Nicholson's 

 Dictionary of Gardening" as the correct 

 name of Tradescantia discolor. 



Rhomboid. Approaching a Rhomb in shape ; 

 applied generally to leaves or petals. 



Rhopa'la. From Roupala, the Guianan name. 

 Nat. Ord. Proteacece. 



A genus of South American trees or large 

 shrubs, having simple or pinnate coarse 

 leaves, conspicuous for their terminal or axil- 

 lary racemes of yellow flowers, which are 

 often covered with a rich brownish wool. A 

 number of the species are under cultivation 

 in the green-houses, but chiefly in botanical 

 collections. 



Rhopalo'stylis. From rhopalon, a club, and 

 stulos, a pillar ; alluding to the club-shaped 

 spadix. A genus of two species of Palms, 

 known in cultivation as Areca Baueri and 

 Areca (Kentia) sapida. 



Rhubarb. See Rheum. 



Rhus. Sumach. Derived from rous in Greek, 

 which is from rhudd, a Celtic word signifying 

 red; alluding to the color of the fruit, and 

 also of the leaves of some species in autumn. 

 Nat. Ord. Anacardiacece. i 



An extensive genus of deciduous shrubs, 

 natives of the United States, Europe, and 

 Asia. They are all interesting from the beau- 

 tiful colors their leaves assume in dying off 

 in autumn. R. Toxicodendron, and its varieties, 

 commonly called Poison Ivy or Poison Oak, are 

 about as dangerous as the fabulous Upas Tree 

 of Java. There is, however, a singular fact 

 connected with this plant that makes it dis- 

 tinctive ; some persons can handle it with 

 impunity, while others, from the slightest 

 touch, or even from the wind blowing over 

 the plant, will have their arms, face and 

 bodies fearfully and painfully swollen by it. 

 The same is true, though in a less degree, 

 when the leaves of Celery or Parsnip are 

 touched by the arms or face when damp. R. 

 venenata or Poison Elder, has so virulent a sap 

 that it is said to occasion fever and inflamma- 

 tion in those who cut it down. One of the 

 most beautiful species is R. cotinus, Mist or 

 Smoke Tree, a native of the south of Europe. 

 It is remarkable for its feathery inflorescence. 

 This species also yields the yellow dye-wood 

 called young Fustic. R. vernicifera, a Japan 

 species, is a small tree, and yields the famous 

 Lacquer so extensively employed by the 

 Japanese for lacquering various articles of 

 furniture and small ware. It exudes from 

 wounds made in the tree, and is at first milky 

 white, but becomes darker, and ultimately 

 black on being exposed to the air. Nothing is 

 known respecting the mode of preparing it ; 



RIB 



that is kept a profound secret, as one of their 

 sources of wealth. R. typhina, the Stag-horn 

 Sumach ; R. copallina, the Dwarf Sumach, and 

 R. glabra, generally called the Smooth 

 Sumach, are all handsome small trees or 

 shrubs, exceedingly useful and valuable in 

 ornamental planting when grown in a mass 

 and kept compact by occasional shortening-in 

 of the more vigorous upright branches. They 

 can be planted also with admirable effect as 

 single specimens upon the lawn, and from the 

 habit common to all the Sumachs, of spread- 

 ing rapidly from underground shoots, they 

 are excellent plants for clothing rocky banks, 

 railroad cuts, and other rough places, where 

 it is desirable to hold the soil from washing, 

 and to shade the ground. There is a variety 

 of R. glabra (var. laciniata), with deeply 

 incised leaflets, discovered many years ago in 

 Chester County, Pennsylvania, which is often 

 seen in our gardens, parks, etc. The various 

 species can be increased from seed, but a sup- 

 ply of young plants can be much more readily 

 obtained by cutting up pieces of the stout 

 roots into pieces two or three inches in length 

 and planting them in nursery rows. Vigorous 

 young plants of a size fit for permanent plant- 

 ing can be obtained by this method in a year. 



Rhyncho'sia. From rhynchos, a beak ; the keel 

 of the flower is beaked. Nat. Ord. Legumi- 

 nosce. 



An extensive genus of herbs and under- 

 shrubs, mostly of a twining habit. They are 

 natives of the West Indies, Mexico, South 

 America, and India, and are plants of but 

 little beauty. R. precatoria has pretty little 

 half-black and half-scarlet or yellow shining 

 seeds, which the Mexicans string into neck- 

 laces and rosaries. 



Rhynchospe'rmum. From rhynchos, a beak, 

 and sperma, a seed. Nat. Ord. Apocynacece. 



R. jasminoides is a very beautiful, free- 

 flowering and sweet-scented green-house 

 climber, a native of India, China, and Japan. 

 In habit it resembles the Jasmine, as its spe- 

 cific name implies. It is a rapid grower, 

 requiring only ordinary green-house culture. 

 A variety with variegated foliage is very orna- 

 mental. It was introduced in 1846, and is 

 propagated by cuttings. Syn. Trachelosper- 

 mum. 



Rib. The principal vein or nervure which pro- 

 ceeds from the petiole into a leaf ; also any 

 firm longitudinal elevation. 



Ribbon Flower. Cape. Spatalanthus speciosits. 



Ribbon Grass. Phalaris arundinacea picta. 



Ribbon Tree. Plagianthus betulinus. 



Ri'bes. Currant, Gooseberry. From Ribas, 

 the name of an acid plant mentioned by the 

 Arabian physicians, and which is known to be 

 Rheum ribes. Nat. Ord. Saxifragacece. 



Our garden varieties of Currants have all 

 originated from R. rubrum, a native of north- 

 ern Europe ; and the same species is also indig- 

 enous- to the swamps of New Hampshire, 

 north, and west to Wisconsin. The berries of 

 this shrub are uniformly red in their wild 

 state. The white, bronze, and other varieties, 

 have been produced under cultivation. To 

 the Dutch we are indebted for the first 

 endeavors to improve this fruit by cultiva- 

 tion, the nurserymen of other nations having 

 paid but little, if any, attention to this branch 



