1 



ROTTBOELLA. 



RUBICELLE. 



Anmali of \atural Ifittory, 1848 ; Gone, On the Anatomy of A'o/ow- 

 mata avrita, in Traniaetioni of Microttvpical Society, 1851 ; Huxley, 

 On Lacimilaria tocialu, in Traruactiont of Microteopical Society, 

 1851 ; Williamson, On Ike Anatomy of Melicerta ringtail, in Quarterly 

 Microscopical Journal, vol. i. ; Gone, On the Jfabitt of Mdicerta 

 rimgrnt, in Quarterly MicroKopical Journal, voL L ; Leydig, On 

 Rotifera, translated in Quarterly ilicrotcopical Journal, vol. ill) 



ROTTBOELLA, a genus of Plants belonging to the tribe Koltbotl- 

 liacecc, of the Tory natural and extensive family of Onuses, named by 

 Mr. Brown in honour of C. F. Rottbull, a professor of botany at 

 Copenhagen, who died in 1797, and who published several works, one 

 in particular on exotic species of Oraminea and Cy/teraceir. The genus 

 is distributed throughout Asia, especially India, Australia, and the 

 tropical islands, and extends also to Egypt. The species are usually 

 tall, erect, and fiat-leaved, with the spikes round and jointed ; spike- 

 leU two in each joint, pressed close to or sunk into a hollow in the 

 rachia ; of these one is sessile, the other stalked. The species are not 

 relished by cattle, with the exception of J!. glabra, of which they are 

 laid to be food in India. 



ROTTEN-STONE, a Mineral, occurring massive. Fracture uneven. 

 Colour grayUh, reddish, or blackish brown. Dull, earthy, and opaque. 

 Soft, soils the fingers, and is fetid when rubbed or scraped. It is found 

 near Bakewell, Derbyshire ; in Wales ; and at Albany, in the state of 

 New York. It is employed in polishing metals, &c. The analysis by 

 R. Phillips gives 



Alumina. 86 



Silica . 4 



Carbonaceous matter 10 



100 



KOTTLK'R A, a genus of Plants named in honour of Dr. Rottler, 

 belonging to the natural family Huphorbiacea. It is characterised by 

 having male and female flowers upon different plants. Male : Calyx 

 3-5-partite; corolla none; stamens 30 to 40, inserted into the convex 

 receptacle ; filaments free or uniftd at the base. Female : Ovary 2-3- 

 4-o-lled, each 1 -seeded ; style deeply 2-3-4-partite, laciniatcd ; capsule 

 2-3-4-coocous, each 1-eeeded. The geuus, which is found in the 

 tropical parts of Asia and throughout India, contains handsome 

 moderate-sized trees. It. tetracocca grows in Silhet, and yields a hard 

 and valuable timber. The capsules of R. tinctoria, a native of the 

 Coromandel coast, and extending to the forests of Northern India, 

 are covered with short stiff hairs, which when rubbed off have the 

 appearance of a powder of a fine red colour, which is employed in 

 India in dyeing silk of a scarlet colour, and therefore forms an article 

 of commerce in that country. Dr. Royle states that this strigose 

 pubescence is also employed in India as an authelmintic in the same 

 way that cowage is, and, like it, probably acts mechanically in 

 expelling intestinal worms. 



ROUD. [LEUCISCUS.] 



ROULOUU [ 



ROUNDTAIL. 

 ROWAN-TREE. [PTRCS.J 



KOXBl'RGHIA. iRoxuuR 



ROXBURGHIACE.E, Kojburyh-Worlt, a natural order of Plants 

 belonging to the class Dictyogens. The species are twining shrubs 

 with tuberous roots ; reticulated leaves, coriaceous, and with parallel 

 teoundary veins connecting several primary ribs ; flowers large and 

 showy, solitary, fcotid ; perianth of four large petaloid divisions ; 

 fctnmens 4, hypogynous ; anthers adnate, opening inwards, pointed, 

 with connectives projecting far beyond the cells, which separate from 

 the latter as far as their bases ; pericarp 1 -celled, 2-valved, with two 

 clusters of seeds at the base. Seeds attached to long cords covered 

 with loose hairs just below the seeds; embryo taper, in the axis of 

 fleshy albumen, with the plumule lying within a slit. The plants of 

 this small order are natives of the hot parts of India, There is but 

 one genus 



Itoj burghia, the roots of a species of which are prepared with lime 

 water, candied with sugar, and taken with tea. The flavour is insipid. 



(Lindley, Vegetable Kingdom.) 



ROYDSIA, an Indian genus of Plants allied to the natural order 

 CV;</.arirfewr, named by Dr. Roxburgh in compliment to Sir J. Royds. 

 The grnua cotisiats of a single species indigenous in the forests of 

 Silhet, where, with a stout stem and numerous branches, it climbs 

 over the trees to a great extent, and flowers in the month of March, 

 diffusing a strong but pleasant odour from its numerous blossoms 

 arranged in axillary racemes or terminal panicles. The leaves are 

 alternate, oblong, coriaceous, smooth on both aider, and without 

 Hipule'. The calyx is 0- partite and of a pale-yellow colour ; corolla 

 none ; stamens numerous, with the filaments inserted on the apex of 

 abort column ; ovary pedicelled, 3-cclled, with two rows of ovules 

 in each, attached to the axi ; drupe berried, of the size of a large 

 olive, orange-coloured ; pulp abundant and yellow; nut oblong, single- 

 celled and 3-valved ; seed solitary, conformable to the nut. The 

 plant is figured in Roxburgh's Coromandel Plants,' p. 289, and is 

 well-suited to the hothouses of this country. 



ROTLEA, a Himalayan genus of Plants belonging to the natural 

 order iamiacetr, and tribe /Mlolar, named by Dr. Wallich in compli- 

 ment to Dr. Royle, author of the ' Illustrations of the Botany of the 

 Himalayan Mountains and of Cubmere,' who first found it on the 



Sirmore Mountains. The plant forms a handsome shrub, with many 

 branches and an abundance of pale-green glaucous leaves. It is 

 characterised by having the calyx ovate, tubular, 10-nerved, and 

 semi-quinquefid ; corolla shorter than the calyx, 2-lipped, lips unequal ; 

 stamens 4, didynamous, ascending under the upper lip ; anthers bilo- 

 cular ; stylo bifid. 



R. elegant, the only species known, is called Putkuroo by the natives 

 of the mountains where it is indigenous, and is employed by them as 

 a febrifuge. It is suited to the shrubberies of this country. 



ROYSTON CROW, the common English name for the Hooded- 

 Crow, Corvui Cornir, Linn. [CoRTiOJE.] 



The subjoined illustration is omitted in the article CORVIDA. 



lloj-ston Crow (Oartia Oirnir}. 



RUBELLAN, a Mineral, which occurs in small hexagonal plates, 

 not elastic. Colour reddish-brown. Hardness 2 to 2'5. Lustre pearly. 

 Transparent, opaque. Specific gravity 2'8 to 3-1. Found at Schima, 

 in the Mittelgebirge, Bohemia. The analysis by Klaproth, gives : 



Silica 45 



Alumina 10 



Oxide of Iron 20 



Lime 10 



Potash and Soda 10 



Volatile Matter 5 



100 



RUBELLITE. [TOURMALINE.] 



RU'BIA, a genus of Plants belonging to the natural order Galiacca:, 

 containing about 40 species, found both in Europe and Asia. This 

 genus is characterised by flowers monopetalous, superior ; tube of the 

 calyx ovate-globose, limb scarcely any ; corolla sub-campanulatc, 

 rotate, 5-partite; stamens 4-5, short; styles 2, short; berries 2, 

 1 -seeded. 



R. linctorum, Madder, has been long known, and was employed in 

 medicine even in the time of Hippocrates, but is valued chiefly as a 

 dye. It has a diffuse brittle-branched stem, angular, very rough, with 

 sharp hooks ; leaves 4 or C in a whorl, lanceolate or oblong-lanceolate, 

 mucronate, somewhat membranous with pinnated veins; flowers 

 small and white ; lobes of the corolla ovate-lanceolate, apiculate ; 

 anthers ovate-oblong ; stigmas conical It is a native of Europe and 

 Asia Minor, but is now extensively cultivated in Holland and France; 

 the culture has likewise been attempted, and successfully, in this 

 country, but the English madder could not be sold so cheap as the 

 foreign ; it is therefore still largely imported, chiefly from Holland, 

 France, Italy, and Turkey, though since cochineal has become cheaper, 

 it is much used for the same purposes. It is employed by dyers and 

 calico printers as a red and scarlet dye. It has also the singular 

 property of turning red the bones and secretions of fowls and other 

 animals fed on it 



R. cordifolia (R. Munjitta), the Munjeetof India, a native of Nepaul, 

 &c., possesses very similar properties, and is imported into England 

 from Calcutta. The root is used as a substitute for that of R. lincto- 

 rum ; it is known in commerce under the name of East Indian Madder, 

 and is also employed in medicine. Like Madder, Munjcet was 

 probably known from very early times, as Rodeen is given as the 

 Greek name in Persian works on Materia Medico, R, Chilcmu and 

 R. Relbun, both natives of South America, are also esteemed there as 

 dyes. 



Liii.ller, Vegetable Kingdom.) 

 RU131CELLK. [SFIMBL.J 



