RHI 



OR, BOTANICAL DICTIONARY. 



465 



ney-shaped, with a brittle shell covered with prickles ; ker- 

 nels solitary, kidney-shaped. ESSENTIAL CHARACTER. 

 Calix: half five-cleft. Petals: five. Germen: four-sided, 

 superior. Nuts: four, one-celled, one-seeded. The spe- 

 cies are, 



1. Rhizobolus Butyrosus. With fingered leaves, smooth 

 on both sides. This is a tall tree, the trunk of which is 

 three feet in diameter. The bark is grey ; and the wood red- 

 dish and compact. The flowers grow in large bunches at the 

 extremities of the branches, and are of a white colour, appear- 

 ing in July; fruit yellowish. Native of Guiana. 



2. Rhizobolus Tuberculosus. With fingered leaves, downy 

 beneath. This tree has thicker leaves than the preceding, 

 downy beneath, a-nd ash-coloured. Fruit larger, and tuber- 

 cled, the pulp dry, not buttery : the nut is sweet and pala- 

 table, containing a rich oil ; and is not unfrequent in fruiterers' 

 shops, by the name of Suwarrow Nut. Native of Guiana. 



Rkizophora; a genus of the class Dodecandria, order. 

 Monogynia. GENERIC CHARACTER. Calix: perianth one- 

 leafed, four-parted or many-parted, patulous; segments 

 oblong, acuminate, permanent. Corolla: petals four or more, 

 oblong, rather shorter than the calix. Stamina: filamenta 

 scarcely any, alternately shorter ; antheree four to twelve, 

 small, acuminate. Pistil: germen superior, roundish ; style 

 awl-shaped, semibifid, grooved on each side ; stigmas acute. 

 Pericarp : fleshy, subovate, enclosing only the base of the 

 seed. Seed: single, club-oblong, acuminate, fleshy at the 

 base. Observe. The stamina differ in number, as do the 

 calix and corolla. ESSENTIAL CHARACTER. Catix: four 

 or five parted. Corolla: four or five parted. Seed: one, 

 very long, fleshy at the base. The species are, 



1. Rhizophora Conjugata. Leaves ovate-oblong, bluntish, 

 quite entire; calices sessile; fruits cylindric-subulate. This, 

 like all the rest of this genus, is a maritime tree. Native of 

 the East Indies. 



2. Rhizophora Gymnorhiza. Leaves lanceolate, quite en- 

 tire ; root plaoed upon the ground. This tree is above the 

 middle size, with a lofty straight trunk : the bark is thick, 

 cloven, of a brown-ied colour; and is very useful in dyeing 

 a rufous or chestnut colour, which is easily changed into a 

 very fine permanent black. Th*re are vast quantities of this 

 tree on the shores of Cambodia and Cochin-china ; and our 

 circumnavigators found it in the islands of the South Seas. 



3. Rhizophora Candel. Leaves obtuse ; peduncles bige- 

 minate, longer than the leaf; fruits awl-shaped. The flowers 

 have a weak, but not unpleasant smelL Native of the East 

 Indies, in shallow salt-water. 



4. Rhizophora Mangle; Mangrove Tree. Leaves acute; 

 fruits subulate-clavate. This tree generally rises to the 

 height of fifty feet: the wood is white, but becomes red when 

 macerated in water; the bark is thick, and rust-coloured. 

 Flowers white, mostly eight-petalled. It is generally found on 

 the borders of the sea, in the waters of which (alone) it seems 

 to thrive. Its larger branches frequently send out soft and 

 weakly appendicles, that have the appearance of so many 

 slender leafless branches, and bend always downwards ; but 

 as these are softer, and furnished each with a large column 

 of lax spongy pith in the centre, they grow more luxuriantly 

 than the other parts of the tree, and reach the mud in a short 

 time, where they throw out a numberless series of slender 

 fibres, which in time become roots to supply the stem more 

 copiously with nourishment, whilst they become so many 

 props or limbs to the parent tree. Thus it continues to 

 enlarge its bulk, as its branches spread ; these constantly 

 throw out new appendicles as they multiply their shoots, and 

 form those iuterwoven groves we so frequently meet with on 



the sea-shore in tropical climates ; which serve to stop the 

 mould that is constantly washed down by the rapid floods that 

 come from the inland parts, and thereby in time turn what 

 might have continued useless ponds or open creeks into rich 

 and fertile fields. The quantity of mosquitoes that frequent 

 these maritime forests make it impossible for an European to 

 ive, or even to pass a night, near them : they are inhabited 

 also by innumerable sea-birds and crabs ; and the matted 

 roots enable the savages to walk about the ooze and shallow 

 waters to hunt for them. The trunk seldom grows to any 

 considerable thickness, but the wood is very tough and hard, 

 bears the water well, and is much used for knees and ribs in 

 long-boats, and other small craft, for which the arches and 

 angles of its limbs most naturally adapt it. The bark is most 

 excellent for tanning leather; it performs this operation more 

 perfectly in six weeks, than Oak-bark will do in ten, and the 

 leather tanned with it is the most firm and durable of any for 

 soles. The decoction of the bark is a most powerful astrin- 

 gent. This tree is a native of both the East and West Indies, 

 of the Society and Friendly Islands, the New Hebrides and 

 New Caledonia, in the South Seas. 



5. Rhizophora Cylindrica. Fruits cylindrical, blunt. This 

 agrees with the second species, except that it is rather taller, 

 and not divided into so many trunks. Flowers white, axil- 

 lary. The fruit is eaten when young and tender: it is green 

 when young, but afterwards reddish-blue. Native of salt 

 marshes in Malabar. 



Rhodiola; a genus of the class Dioecia, order Octandria. 

 GENERIC CHARACTER. Male. Calix: perianth four- 

 parted, concave, erect, obtuse, permanent. Corolla: petals 

 four, oblong, obtuse, from erect spreading, double the length 

 of the calix, deciduous; nectaries four, erect, emarginate, 

 shorter than the calix. Stamina : filamenta eight, awl-shaped, 

 longer than the corolla ; antheree simple. Pistil: germina 

 four, oblong, acuminate ; styles and stigmas obsolete. Peri- 

 carp: abortive. Female. Calix : perianth as in the male. 

 Corolla: petals four, rude, erect, obtuse, equal with the calix, 

 permanent; nectaries as in the male. Pistil: germina four, 

 oblong, acuminate, ending in simple straight styles; stigmas 

 obtuse. Pericarp: capsules four-horned, opening inwards. 

 Seeds: very many, roundish. Observe. Dahl having ob- 

 served hermaphrodite flowers with ten stamina and five styles, 

 is of opinion this genus should be associated with Sedum. 

 ESSENTIAL CHARACTER. Male. Calix: four-parted. Co- 

 rolla : four-petalled. Nectaries : four. Female. Calix and 

 Nectaries: like the male, but smaller. Petals: of a coarse 



texture. Capsules: four, many-seeded. The species 



are, 



1. Rhodiola Rosea; Common or Yellow Roiewort. Leaves 

 ovate, serrate towards the top. Stem upright; root thick 

 and fleshy, sending out, when bruised or cut, an odour like 

 roses ; (he flowers are yellowish and herbaceous, appearing 

 early iti May: they have a very agreeable scent; but are 

 not of long continuance. The root is sweetest when dried, 

 in which state a fragrant water may be distilled from it ; but 

 when cultivated in a garden, it loses most of its odour. 

 Goats and sheep are said to eat the plant, but cattle and 

 swine refuse it. The inhabitants of the Faro Islands use it 

 as a remedy for the scurvy ; and the Greenlanders eat it as 

 garden-stuff. A cataplasm of the fresh roots, applied to the 

 forehead, is said to relieve the headache; also to cure malig- 

 nant ulcers. There is a variety which flowers later. Native 

 of Lapland, Denmark, and Norway, Great Britain, Austria, 

 Silesia, Switzerland, Dauphiny, Piedmont, and Siberia, on 

 the mountains of those countries. In England it occurs only 

 in the northern counties of Westmoreland, Cumberland, and 



