578 



ROSCOEA RUBY. 



ciflorce. This order contains forty-six genera, and not 

 less than seven hundred and eighty-three species. 

 Whether the genera be trees, shrubs, or herbs, there 

 is a similitude in the character of their flowers which 

 is obviously striking ; and the single rose being a 

 type so well known, facilitates the identification of 

 the various genera. Among the trees there are the 

 Amygdalus, Primus, Persica, Cerasus, and Eriobotrya, 

 which are also fruit bearers ; among the shrubs, be- 

 sides the type, there are the Cratcegus, Photinia, 

 Cotoneaster, and Cydonia; and among herbs we have 

 the useful strawberry, the Potcntilla, Geum, and 

 Tormentilla. 



Rosacece is divided into eight tribes, viz., Chryso- 

 balanece, Amygdalete, Spiracece, Neuradeae, Dryadcce, 

 Sanguisorbece, Ro&ece, and Pomaccce, The Amygdalece 

 is distinguished from the other Ro&aceee, because it is 

 remarkable for containing plants which, notwith- 

 standing they all bear eatable fruits, furnish from 

 their leaves, their blossoms, and even from their 

 seeds, one of the most subtile and powerful vege- 

 table poisons known. The deleterious principle, 

 separated by modern chemistry and named prussic 

 acid, although so poisonous in a concentrated form, 

 rarely exists in such proportion to the sugar, muci- 

 lage, and other innocuous substances, with which it 

 is naturally combined, as to be in any degree inju- 

 rious. Hence, bitter almonds, peach and plum stones, 

 and cherry-laurel leaves, have been favourite ingre- 

 dients with cooks and confectioners to give a pleasant 

 flavour to custards, puddings, and jellies ; and several 

 of our most excellent liqueurs, such as noyau, ra- 

 tafia, and maraschino, owe their flavour to this subtile 

 poison. 



The rose, the strawberry, and their associates are 

 herbaceous or shrubby, but never arborescent plants, 

 with alternate leaves, either simple or compound, 

 and almost universally furnished with stipules. The 

 inflorescence is variable, the flowers monoclinous, 

 rarely by abortion separated ; very prone to become 

 double, and in colour red, white, or yellow, but never 

 blue ; the calyx of four or five sepals, and more or 

 less connected ; the fifth or odd lobe being axial or 

 posterior ; the torus is variable, sometimes forming an 

 annular disk, at others becoming large and hemisphe- 

 rical, or lining the urceolate tube of the calyx ; the 

 petals are equal, with short claws, perigenous, five in 

 number, and rarely absent ; the stamens are inde- 

 finite ; the filaments free ; anthers innate, two-celled, 

 and opening lengthwise ; the ovaries are several, 

 superior, and mostly free, one-celled and one-seeded ; 

 the styles are lateral, exserted just below the apex of 

 the carpel, and the stigma simple ; the fruit either 

 one-seeded^nuts or akenia, occasionally becoming 

 drupeolffl. This description is applicable to the 

 strawberry, bramble, raspberry, dewberry, cloud- 

 berry. &c. 



ROSCOEA (Smith). A genus of Nepalese her- 

 baceous plants, belonging to Scitaminea. The species 

 thrive in loam and peat-earth, flower freely, and are 

 increased by division. 



ROSE ACACIA is the Robinia hispida of Lin- 

 naeus, one of our most ornamental shrubbery plants. 

 They are usually propagated by grafting on the com- 

 mon R. pseudacacia. By pruning back the shoots 

 which bear the first flowers, they may be made to 

 flow.er a second time in the autumn. 



ROSMARINUS (Linnaeus). A genus of two 

 species, bearing diandroua flowers, and belonging to 



the natural order Labiate. The R. (rffic'mahs is a well 

 known aromatic-scented plant, for which it has been 

 long cultivated in gardens. Burnett says it gives 

 its fragrance to Hungary-water ; it is likewise one of 

 the ingredients employed in the manufacture of eau- 

 de-Cologne, and it enters into the composition of four 

 thieves' vinegar, once so famed for its supposed power 

 of preventing the spread of contagious diseases. 

 Rosemary has some reputation as a cephalic medi- 

 cine, relieving the headach, and exciting the mind to 

 vigorous action. Hence it has been called the herb 

 of memory and repentance. Hence also its use as a 

 symbol of fidelity, and its introduction both into 

 wedding-garlands and funeral-wreaths ; and still in 

 many of our distant counties it is customary with the 

 mourners to wear sprigs of the plant, and strew them 

 on the grave. 



ROTTLERA (Roxburgh). A genus of ever- 

 green shrubs, natives of the East Indies and Brazil. 

 The flowers are dioecious, and the genus belongs to 

 Euphorbiacece. The R. tinctorea is in our stove 

 collections, and succeeds with the ordinary manage- 

 ment. 



ROXBURGHIA (Jones). An East Indian 

 climbing plant, bearing some resemblance to the 

 Gloriosa superba, hence it is named R. gloriosoides. It 

 belongs to the eighth class of Linnaeus, and to the 

 natural order Asphodelece, increased by division. 



RUBIACEjE. A large natural order containing 

 seventy-three genera, and above three hundred and 

 eighty-seven species. The order is divided into nine 

 sections under the following titles, viz., Guettardece, 

 Hameliacece, Cinchonece, Cephalanthece, Hcdyotidece, 

 CoffeacecE, Spermacocece, and Galece. The Rubiacece, 

 collectively considered, are herbaceous plants, with 

 square or angled stems, and whorled exstipulate 

 leaves ; the verticilli being formed of two opposite 

 gemmiferous leaves, with a variable number of inter- 

 mediate ones, not varying in appearance from the 

 general foliage, but destitute of buds ; hence being 

 stipulaceous, and supplying the place of the iriter- 

 petiolar stipules of the Cinchonacea. The inflores- 

 cence is paniculate, the flowers small, and in general 

 united. The calyx is superior, the tube joined to the 

 germen, and the limb from four to six-clefted ; the 

 corolla is synpetalous, rotate, or funnel-shaped, regu- 

 lar, with its petals equal to the sepals, and exserted 

 from the calyx ; the stamens are equal in number to 

 the lobes of the corolla, and exserted alternately 

 with them ; the filaments are free, the anthers incum- 

 bent two-celled and open longitudinally ; the germen 

 consists of two connate carpels, invested by the ad- 

 herent tube of the calyx ; the styles two, and the 

 stigma headed. The roots of the Rubiaceae often 

 contain a large quantity of colouring matter. This 

 is epecially abundant in the madders, and several 

 species of Galium. Madder is not much grown in 

 this country, although the climate is suitable, because 

 the imported madder is cheaper. Cattle fed on several 

 of these plants have their secretions tinged with the 

 colouring matter. 



There are many beautiful as well as useful plants 

 comprised in this order ; of the first we may notice 

 the Gardenia, Ixora, and Portlandia; of the second 

 the Cinchona, Jesuit's bark, as a medicine, and the 

 coffee as an article of diet, as examples ; although 

 these are associated with many unemployed plants. 



RUBY. This beautiful mineral is, in fact, but a 

 peculiar modification of corundum. Next to the dia- 



