ROYENA 



RUBUS 



3021 



lucida, Linn. Tender evergreen shrub, 4-12 ft. high, 

 or a small tree: bark nearly smooth, dusky gray or 

 whitish: Ivs. oval or somewhat ovate, leathery, shining 

 above, more or less hirsute beneath: fls. solitary, 

 axillary, white or yellowish; calyx 5-toothed; corolla- 

 tube urceolate, limb reflexed, 5-parted, puberulous; 

 segms. rounded: fr. ovoid or subglobose, red or purple 

 and fleshy when ripe. S. Afr. B.R. 32:40. 



F. TRACT HUBBARD. 



ROYSTt>NEA: Oreodoxa. 



RUBBER PLANTS. Various plants furnish rubber. 

 The best gutta-percha is said to be produced by Isonan- 

 dra Gutta (which see), a native of India. For the rub- 

 ber tree of South America, see Hevea, brasiliensis. The 

 rubber tree of tropical Africa is Landolphia florida; see 

 B.M. 6963. The rubber plant of horticulturists is 

 F icus elastica. For an agricultural account of rubber, 

 see ''Cyclopedia of American Agriculture," Vol. II. 



RUBIA (Latin, red; referring to the color of the dye 

 extracted from the root). Rubiacese. Mostly hardy 

 herbs, sometimes shrubby at base, of little horticultural 

 worth, but one, R. tindoruin, is of economic value. 



Plants frequently rather stiff, hispid, or aculeate: 

 Ivs. in whorls of 4-8 or very rarely opposite and stipu- 

 late, sessile or petioled, lanceolate or obovate, rarely 

 cordate: fls. small or minute, in axillary or terminal 

 cymes, 5-merous; involucre none; calyx-tube ovoid or 

 globose, limb lacking; corolla rotate or subcampanu- 

 late; ovary 2-celled or through abortion 1-celled: fr. 

 didymous, fleshy. 2- rarely 1-celled. About 40 species, 

 Medit. region, Trop. and S. Afr., Temp. Asia, Trop. 

 and S. Temp. Arner. R. tinctorum is the dye-plant 

 called madder, the long, fleshy roots of which are 

 ground to powder. Madder is said to furnish a good 

 green fodder if cut the second year when in flower. 



tinctSrum, Linn. (R. tinctoria, Salisb.). MADDER, A 

 scandent herbaceous perennial: Ivs. 24 in. long, sessile 

 or very short-petioled, mostly lanceolate, not cordate, 

 in whorls of 4-6: cymes terminal, panicled, spreading, 

 leafy. F. W. BARCLAY. 



F. TRACT HUBBARD.! 



RUBUS (Latin name, ultimately connected with 

 ruber, red). Including Bossekia, Rubacer, Oreobatus, 

 Batidsa, and others, but excluding Dalibarda. Rosac&e. 

 BRAMBLE. BLACKBERRIES, DEWBERRIES, RASPBERRIES, 

 and THIMBLEBERRIES. Low and diffuse mostly woody 

 plants, usually producing canes, grown for the edible 

 fruits, some of the species for ground-cover, and others 

 for the more or less ornamental character of habit, 

 foliage, and bloom. 



Trailing, decumbent, ascending, or erect plants, the 

 tips of long growths usually recurving even if other- 

 wise erect, glabrous, hairy or variously glandular, 

 mostly thorny or prickly: sts. usually short-lived and 

 pithy (sometimes semi-herbaceous): Ivs. simple or 

 compound, alternate, the compounding on the pinnate 

 order and the leaflets largely 3 (several in many of the 

 tropical and oriental species) : fls. mostly white or rose- 

 colored, usually in corymbs or racemes but sometimes 

 solitary; calyx 5-parted (rarely 3-5-parted), the lobes 

 persistent; petals 5, usually obovate; stamens many, 

 inserted on the torus-rim; pistils many (or sometimes 

 few), closely packed on the torus, usually becoming 

 drupelets but sometimes dry when ripe, the style 

 nearly terminal. A most variable and perplexing genus, 

 containing perhaps 400 fairly well-marked species 

 and numberless intermediate forms. More than 3,000 

 species-names have been applied. The genus is par- 

 ticularly strong in Europe, where great numbers of 

 specific names have been made (see Weihe & Nees, 

 Rubi Germanici, 1822-7; Focke, Synopsis Ruborum 

 Germania, 1877; Babbington, British Rubi, 1869; 

 Focke, in Ascherson & Graebner, Synopsis der Mittel- 



europaischen Flora, 1902; Rogers, Handbook of British 

 Rubi, 1900, and many other publications). Focke in 

 1877 described 72 species inhabiting Germany. In 1902 

 he admitted 87 full species to the mid-European flora. 

 There is also a large extension of the genus in the 

 Himalayan region, about 50 species being recognized 

 (J. D. Hooker admits 41 species in the Flora of British 

 India). The species extend eastward into China and 

 Japan. Hemsley, in his Flora of China, admits 41 

 species. In Japan, Franchet and Savatier admit 22 

 species. In the North American Flora, Rydberg 

 admits 112 species, in 1913, counting those in Mexico 

 and southward and excluding certain species that are 

 referred to other genera. Students of the American 

 forms should consult the recent writings of Blanchard, 

 Brainerd, Bicknell, and Rydberg. There is no agree- 

 ment as to the number of species in N. Amer. or else- 

 where, and recently other genera have been segregated. 

 Rubus is widely distributed in the northern hemi- 

 sphere, particularly in temperate and warm-temper- 

 ate parts. Some of the species are alpine and arctic. 

 In tropical climates the genus is relatively poorly repre- 

 sented. Oliver admits only 4 in the Flora of Tropical 

 Africa. Only 2 species are described in Grisebach's 



/i $?p^3j^. 



3486. An English raspberry-blackberry hybrid. (XJ'i) 



Flora of the British West Indies. Baker admits 3 

 species in the Flora of Mauritius and the Seychelles. 

 Hillebrand describes 3 species in Flora of the Hawaiian 

 Islands. The southern hemisphere has few species. 

 Bentham's Flora Australiensis has but 5 species. 

 Cheeseman's Manual of the New Zealand Flora men- 

 tions only 4 indigenous species. There are also 5 species 

 described in Harvey and Sender's work (Flora Capensis) 

 on the flora of the Cape of Good Hope region. In his 

 Species Ruborum (Bibl. Bot. parts 72 and 83. 1910-14), 

 Focke describes 429 or more species from all around 

 the world. 



The genus Rubus tempts the species-maker. The 

 lines of demarcation are obscure or indefinite, the 

 variables are numberless, the botanical characters differ 

 widely on old and young canes and even on spring and 

 autumn foliage of the same cane, and the plants 

 respond readily to conditions. There are marked shade- 

 forms and sun-forms, moisture-forms and dry-land 

 forms, apparently only environmental modifications of 

 prevailing types. The tendency, therefore, on the one 

 hand is to recognize a very few stem-types as species 

 (Bentham reduced all the British rubi of the blackberry 



