ROL 



OR, BOTANICAL DICTIONARY. 



RON 



479 



1. Roella Ciliata; Ciliated Roella. Leaves lanceolate, 

 ciliate ; flowers subsolitary, terminating;. This is a low 

 shrubby plant, somewhat like Heath -when in flower. When 

 the flower is recently expanded, five shades of colour appear, 

 which, being disposed in circles, produce a striking effect ; 

 the bottom of the flower is white, of a yellowish cast ; next suc- 

 ceeds a circle of deep blue inclining to black, with a surface 

 highly glazed ; the next circle is a grayish-blue, resembling 

 satin ; the next nearly white ; and the outermost pale purple. 

 It flowers in June, and continues several weeks. Native of 

 the Cape of Good Hope, and of Barbary. This, and also 

 the other shrubby species of this genus, may be increased by 

 cuttings, but not very readily. They are not so easy of 

 culture as many other plants, and must be kept in a dry- 

 stove, good green-house, or glass-case. 



2. Roella Squarrosa; Trailing Roella. Leaves ovate, 

 toothed, ciliate; flowers terminating, aggregate. Stem her- 

 baceous, diffuse. It flowers in June. Native of the Cape. 



3. Roella Decurrens ; Decurrent Roella. Leaves lan- 

 ceolate, quite entire, decurrent; flowers solitary, terminat- 

 ing. It flowers in September. Native of the Cape. 



4. Roella Muscosa; Mossy Roella. Herbaceous, diffused : 

 leaves ovate, toothed, reflex; flowers terminating, solitary. 

 A very small annual species. Native of the Cape. 



5. Roella Spicata; Spiked Roella. Leaves lanceolate, 

 ciliate ; flowers terminating, aggregate. Stem shrubby, erect. 

 Native of the Cape. 



Rohria; a genus of the class Triandria, order Monogynia. 

 GENERIC CHARACTER. Calix: perianth one-leafed, bell- 

 shaped, five-parted ; segments ovate, concave, blunt, ciliate, 

 coriaceous; the two inner ones a little longer. Corolla: 

 petals five, upright, longer than the calix, the two upper 

 ones a little larger, the three lower smaller; claws narrow, 

 widf r at the base, woolly within, a little bent outwards under 

 the border, which is ovate, erect, in the larger petals bent 

 inwards and cowled, in the smaller spread out and bluntish. 

 Stamina : filamenta three, one between the two larger petals, 

 and two by the side of them, united at bottom with their 

 claws, all filiform, longer than the corolla, woolly within ; 

 antherae roundish, erect, directed inwards. Pistil : germen 

 turbinate, tomentose; style filiform, the length of the sta- 

 mina, villose ; stigmas three, revolute. Pericarp: doubtful 

 whether a capsule or nut. Seeds: not ascertained. ESSEN- 

 TIAL CHARACTER. Calix: bell-shaped, five-parted. Corolla: 

 five-petalled, unequal. Stigmas: three, revolute. Capsule? 



The only known species is, 



1. Roliria Petioliflora. A shrub, about twelve feet in 

 height, with many flexible, roundish, smooth branches. 

 Leaves alternate, petioled, oblong, acuminate, quite entire, 

 netted, veined, about four inches long ; flowers small and 

 yellow. Native of the woods of Guiana. 



Rolandra ; a genus of the class Syngenesia, order Poly- 

 gamia-Segregata. GENERIC CHARACTER. Calix: common 

 none ; florets in bundles, in a roundish head ; bundles dis- 

 tinct, pedicelled, with many scales interposed, shorter than 

 the florets, ovate and lanceolate, awned ; partial perianth 

 chaffy, two-valved ; valves unequal, compressed, keeled, the 

 upper one larger, enclosing the other, awned; lower acumi- 

 nate. Corolla: proper, Hermaphrodite, very small, funnel- 

 shaped; tube filiform, long; border five-cleft; segments 

 very short, erect, acute. Stamina: filamenta five, shorter 

 than the tube; anthera tubular within the aperture. Pistil: 

 germen compressed, three-cornered, acute at the base, retuse 

 at the top ; style the length of the tube, bifid at the top ; 

 stigmas tumid, erect. Pericarp : none, the seed being en- 

 closed in the unchanged partial calix. Seeds: three-cornered, 

 VOL. it. 106. 





crowned with a toothed rim. ESSENTIAL CHARACTER. 

 Common Calixj none. Perianth: two-valved, single-flow- 

 ered. Florets : hermaphrodite. Seed: with a toothed crown. 

 The only l^nown species is, 



1. Rolandra jArgentea. Stem straight, woody, covered 

 with a smooth reddish-brown bark ; having at every inch or 

 two, one, two, or three leaves, greater and smaller, the largest 

 about two inches long, and three quarters broad in the mid- 

 dle, smooth, d^rk-green on the upper side, and very white 

 underneath, on ;. short footstalk ; flowers in small, round, ses- 

 sile, solitary, axillary, whitish heads. Native of theW. Indies. 



Rondelctia; a.genus of the class Pentandria, order Mono- 

 gynia. GENERIC CHARACTER. Calix: perianth one-leafed, 

 superior, five-parted, acute, permanent. Corolla : one-petal- 

 led, funnel-shaped; tube cylindrical, longer than the calix, 

 bellying a little at top ; border five-parted, from reflex flat ; 

 segments roundish. Nectary a crenate rising in the orifice. 

 Stamina: filamenta five, awl-shaped, almost the length of 

 the corolla; antherse simple. Pistil: germen roundish, infe- 

 rior; style filiform, the length of the corolla; stigma bifid. 

 Pericarp: capsule roundish, crowned, two-celled. Seeds: 

 two or more in each cell, rarely solitary. ESSENTIAL CHA- 

 RACTER. Corolla { funnel-shaped, nectariferous at the mouth. 

 Capsule: two-celled, inferior, many-seeded, roundish, crown- 

 ed with the calix. The species are, 



1. Rondeletia Americana. Leaves sessile ; panicle dicho- 

 tornous. Stalk woody, ten or twelve feet high, branching out 

 on every side ; the branches covered with a smooth greenish 

 bark ; the flowers come out in bunches at the end of the 

 branches, are white, and have little scent. They appear in 

 autumn, but are not followed by seeds in England. Native 

 of the Spanish West Indies. All the plants v of this genus 

 being very tender, require a warm stove in our climate. 

 They are propagated by seeds, which should be sown on a 

 hot-bed early in the spring; and when the plants are come 

 up and fit to removq, they must be planted in separate small 

 pots, and plunged into a moderate hot-bed of tanners' bark, 

 and be treated in the same manner as other tender West 

 Indian Plants. In winter, place them in the tan-bed in the 

 stove, where they will thrive, and in two or three years will 

 flower^ and form an agreeable variety amongst other tender 

 exotic plants, as they retain their leaves all the year. 



2. Rondeletia Odorata. Leaves petioled, subovate, blunt; 

 flowers cymose, three-cleft, terminal. This is an inelegant, 

 irregular shrub, five or six feet high ; branches round, the 

 younger ones villose ; flowers handsome, scarlet, with the 

 projecting rim of the tube orange-coloured, smelling very 

 sweet like violets. Native of the West Indies, where it is 

 not very common ; Jacquin observed it at the Havannah, in 

 rocky coppices near th% coast, growing frequently on the 

 vary naked rocks. It flowers in January, and is, at the same 

 time, loaded with ripe seeds. 



3. Rondeletia Trifoliata. Leaves tern, tomentose under- 

 neath ; panicles axillary. This is an upright tree, twelve feet 

 high. Native of America. 



4. Rondeletia Virgata. Leaves roundish ; branches fili- 

 form, spreading; peduncles trifid; flowers three together, 

 clustered, four-stamined. This shrub is six feet high, with 

 very long, alternately spreading, unarmed branches, with a 

 rugged bark. It flowers and fruits in December. Native of 

 Hvspaniola, in maritime coppices towards the north. 



5. Rondeletia Pilosa. Leaves ovate, hairy, on both sides ; 

 peduncles axillary, shorter than the leaves, trifid ; flowers 

 four-stamined. A shrub, whose branches are round or four- 

 cornered ; corolla salver-shaped ; tube cylindrical. Native 

 of Santa Cruz and Montserrat, in the West Indies. 



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