286 



THE DICTIONARY OF GARDENING, 



Rhamneae continued. 



sometimes changed to thorns. The most useful genera, 

 from an economic point of view, are Rhamnus and Zizy- 

 phus, the species of which yield medicinal juices, &o. 

 Rhamnus davuricus and : R. tinctorius yield the famous 

 Green Indigo, the Lo-Kao of China. The order com- 

 prises thirty-seven genera, and about 430 species. Ex- 

 amples : Hovenia, Paliurus, Pomaderris, and Rhamnus. 



RHAMNUS (from Rhamnos, the old Greek name 

 used by Theophrastus). Buckthorn. Including Frangula. 

 OBD. Rhamnece. A genus embracing about sixty species 

 of stove, greenhouse, or hardy shrubs or trees, inhabiting 

 temperate and tropical regions. Flowers axillary, race- 

 mose or oymose; calyx fouror five-cleft, the tube urceolate, 

 the lobes keeled within ; petals four or five, cucullate or 

 flat, or wanting; stamens four or five; filaments very 

 short. Drupe berry-like, oblong or spherical, two or 

 four-stoned. Leaves alternate, rarely sub-opposite, pe- 

 tiolate, deciduous or evergreen, penninerved, entire or 

 toothed ; stipules small, deciduous. Several of the species 

 afford useful products, especially dyes, and the fruits of 

 many possess violent purgative properties. Few of the 

 plants are valuable from a garden standpoint. The hardy 

 kinds grow in any ordinary soil, and may be propagated 

 by layers, or by seeds. The stove and greenhouse 

 species are easily grown in any light soil, and may 

 be multiplied by cuttings, inserted in sand, under a glass 

 (the stove kinds in heat). Except where otherwise stated, 

 the under-mentioned species are hardy, deciduous shrubs. 

 R. Alaternus (Alaternus). /. green, dioecious, disposed In short 

 racemes ; petals wanting. April to June. I. ovate-elliptic or 

 lanceolate, coriaceous, quite smooth, serrated, h. 20ft. Medi- 

 terranean region, 1629. There are several varieties of this 

 species, the best being one with foliage broadly margined with 

 silvery-white : this is known under the name of R. A. varieyata. 

 R. alpinus (alpine), fl. greenish, dioecious, four-parted ; female 

 ones with four-cleft stigmas. May and June. fr. black. I. oval- 

 lanceolate, crenate-serrated, smooth, lined with many parallel 

 nerves. h. 4ft. Europe, &c., 1752. (L. B. C. 1077.) 

 R. californicus (Californian). fl. greenish, pentandrous ; panicles 

 on short peduncles. May. I. coriaceous, about 2in. long, 

 elliptic-oblong, entire, revolute on the margins, glabrous ; young 

 ones pubescent, h. 6ft. to 12ft. North America, 1874. An un- 

 armed evergreen shrub. SYN. R. oleifolius (H. F. B. A. i. 44). 



Fio. 361. FLOWERING AND FRUITING TWIGS OF RHAMNUS 



CATHARTICUS. 



R. catfcarticus (cathartic), fl. green, iin. in diameter, four- 

 parted, solitary and fascicled in the axils of the fascicles of 

 leaves on the previous year's wood. May to July. fr. black, iin. 

 in diameter. I ovate, acutely-serrated, Iin. to 2Jn. long, fascicled 

 at the ends of the shoots, sub-opposite lower down, shortly 

 petiolate, the young ones downy beneath, h. 5ft to 10ft 

 Europe (Britain), &c. See Fig. 361. (F. D. v. 850 ; SyVEn. B. 318.) 



R. croceus (yellow), fl. greenish, in axillary clusters pentandrous 

 petals waning May. fr greenish or yellowish ' T coriaceous: 

 roundish-obovate, about iin. long, lucid ; when dry, of a bright 

 yellowish-brown beneath, h. t. California, 1848 A much- 

 branched, thorny, evergreen shrub. (J. H. S. vi., p. 217.) 



R. davuricus (Dahurian). fl. greenish - yellow, four -parted 

 numerous, fascicled in the axils. May. I. glabrous fascicled at 

 the ends of the exceedingly congested branchlets f into 2Hn 

 long, obovate, acuminate, to narrow elliptic-lanceolate. Spines 

 terminating the divaru-ating branches, h. 15ft. to 20ft. China, 

 .Eastern Siberia, &c., 1817. Tree or shrub. SYN. ' 



Rhamnus continued. 

 R. d. hirsutus (hairy). I. 2in. long. 



A large shrub or small tree. 



R. Frangula (Frangula). Berry-bearing Alder, fl. greenish- 

 white, five-parted, few, axillary. May and June. fr. black, iin. in 

 diameter, globose. I. obovate, quite entire, alternate ; stipules 



. 



to 6in. long. 

 g above, pale 

 hina (?), 1876. 



FIG. 362. FLOWERING AND FRUITING TWIGS OF RHAMNUS 

 FRANGULA. 



subulate. Branches slender, unarmed, h. 5ft. to 10ft. Europe 

 (Britain), &c. The wood, called Black Dogwood, is used by 

 gunpowder-makers. See Fig. 362. (Sy. En. B. 319.) 

 R. latifollus (broad-leaved), fl. greenish, hermaphrodite ; calyx 

 villous, four-parted ; stigma slightly three-cleft. July. I. elliptic, 

 acuminate, quite entire, lined with twelve or fifteen lateral 

 nerves; younger ones villous. h. 5ft. Azores, 1778. (B. M. 

 2663; W. D. B. i. 11.) 



R. libanoticus (Lebanon), fl. yellowish, fasciculate. May. 

 1. clustered at the tips of the branchlets, slightly tomentose, 

 shortly petiolate, ovate or oblong, obtuse, rounded at base, 

 margin finely denticulate. Branches clothed with whitish bark. 

 h. 6ft. Asia Minor and Syria, 1879. Plant unarmed. The 

 foliage turns a dull bronzy-purple in autumn. (B. M. 6721.) 

 R. macrophyllus (large-leaved), fr. black. I. 5in. to 6in 

 2Jin. to Sin. broad, coriaceous, dark green and shining 

 and strongly veined beneath ; petioles purplish. Chi 

 R. oleifolius (Olive-leaved). A synonym of R. californicus. 

 R. robustus (strong), fl. green, small. May. fr. black, globose, 

 iin. in diameter. I. broadly ovate-lanceolate, convex, 7in. to 8in. 

 long, 3in. to 3in. broad, coriaceous, dark green, h. 18ft. 1879. 

 A very vigorous tree. 

 R. utilis (useful). A synonym of R. davuricug. 



RHAPHIDOFHORA (from rhaphidos, a needle, 

 and phero, to bear; alluding to the needle-like hairs 

 which abound in the intercellular spaces in all parts 

 of the plants). SYN. Raphidophora. OKD. Aroidece 

 (Aracece). A genus comprising about thirty species of 

 slender or robust, climbing, stove shrubs, with very long, 

 rooting branches, natives of tropical Asia, the Malayan 

 Archipelago, Australia, and the Pacific Islands, with a 

 few African. Flowers dense, on a sessile, inappendi- 

 culate, usually hermaphrodite, thick, cylindrical spadix; 

 spathe thick, boat-shaped, including the spadix, at first 

 oblong and convolute, afterwards opening, often rostrate, 

 marcescent, at length deciduous ; peduncles terminal, 

 solitary or many. Leaves distichous, nnequilateral, often 

 large, lanceolate or ovate-oblong, entire, perforated, or 

 pinnatifid, rarely pinnatipartite ; segments broad at base ; 

 petiole short or elongated, long-sheathed. The species 

 described below are those best known to gardeners. A 

 compost of rich loam and fibrous peat, in equal parts, 

 is admirably suited for their culture. The plants should 

 be placed in the border, near a wall or a dead stem of 

 a tree, so that their climbing propensities may be 

 encouraged. A moist atmosphere is essential to success. 

 Propagation may be effected by seeds ; or by cuttings, 

 inserted in sandy loam and peat, under a hand glass, 

 with bottom heat. 



R. decursiva (decurrent). /., spathe yellowish, pale on the 

 margins, very thick, longer than the petiole ; spadix greyish- 

 green, long and thick. I. oblong, unequally pinnatisect as far as 

 the midrib ; segments, on adult leaves, fifteen or more on each 

 side, sub-equal, linear ; petioles one-third shorter than the 

 leaves. India, &c., 1859. 



