RAP\NILLA 



737 



RHAMNUS 



RETANTlMcUM. \ Peruvian name. Nat. ord. 

 RhamnaJs [?. ord. C/*l- Liu"- $-Pfntandria, i-A/ono- 

 gynia. Allied -*. MS Wtetia.) 



Evergreen shrub?. Cuttings of young shoots in sand, 

 under a glass, in summer ; sandy loam and fibrous peat. 

 R. obcorda'ta. requires a warm greenhouse, and R. Ephe'dra 

 the protection of a cold pit in winter, or a very sheltered 

 situation out of doors, or against a wall. 

 R. Epht'dra (Ephedra-like). 3- Cream. Peru. 1823. 

 obcoTda'to (re versed- heart-leaved). 2. Yellow. Peru. 

 1822. 



RETARDING requires as much skill as forcing, for as 

 the latter requires the application of all that is suitable 

 to the promotion of a plant's rapid healthy growth, so 

 retarding requires the withholding from it of those con- 

 tingencies. Thus to retard growth, the lowest tempera- 

 ture, and the least degree of light compatible with healthy 

 growth, must be secured ; and to this end plants for 

 succession are often placed on the north side of a wall. 

 See SCREENS. 



Then, again, as in the case of raspberries and straw- 

 berries, plants are often cut down in the spring, com- 

 pelling them to form fresh foliage and stems, and thus 

 be productive in the autumn instead of the summer. 



The vegetation of many bulbs may be prevented by 

 merely keeping them dry, and, indeed, the withholding 

 the usual supply of water, giving it only in diminished 

 quantities, is necessary in all retarding 'treatment. To 

 secure the entire resting of bulbs, and of such plants as 

 will bear so low a temperature, the atmosphere of the 

 ice-house is effectual ; and to this end it should have a 

 few shelves for the support of boxes or flower-pots. 

 Banks of earth ranging east and west, and facing the 

 north at a very acute angle, are very useful in retarding 

 the early advance to seed in hot weather of spinach, 

 lettuces, &c. Espaliers ranging similarly, and shaded 

 during the whole of March and the two following months, 

 will blossom later and more unfailingly than trees more 

 exposed to the sun in spring. Similar exclusion of heat 

 and light retards the ripening of picked fruit, and if the 

 air be excluded from them, or its oxygen withdrawn, 

 fruit will remain unripened for weeks. To effect this, 

 put a paste formed of lime, sulphate of iron, and water, 

 at the bottom of a wide-mouthed glass-bottle, then a 

 layer of large pebbles to keep the fruit from the paste, 

 then fill the bottle with peaches, apricots, or plums, 

 gathered a few days before they are ripe, cork the bottle 

 tight, and cover the cork with melted resin. They have 

 been thus kept for a month, and summer apples and 

 pears for three months. They ripen when again exposed 

 to the air. 



RETTNIA. The Pine-bud Tortrix Moth (R. luriona' na) 

 is very injurious to the buds of the Scotch Fir and other 

 species of Pinus, as well as the Silver Fir, by feeding 

 inside them, and when the terminal bud of the tree is 

 thus destroyed, the tree is ruined owing to the want of 

 a proper leader. The moth lays her eggs in J uly, chiefly 

 on trees five to fifteen years old. The caterpillars feed 

 in the buds and gnaw their way up the centre of the 

 central bud in autumn, and hibernate there. During 

 April, May, and June they feed again. The caterpillars 

 are purple-brown, with a black head and other markings. 

 The perfect moth hatches out in the July following to 

 repeat her depredations. The average expanse of the 

 fore-wings is three-fourths of an inch, and rusty red or 

 tawny, with silvery markings. 



The Pine-shoot Tortrix Moth (R. buolia'na) is very 

 similar, but its methods of feeding are different. The 

 female lays her eggs amongst the buds terminating the 

 branches, and the small caterpillars hatch out late in the 

 season, when they gnaw the buds, causing an exudation 

 of resin. Under this and a web of their own weaving 

 they hibernate till the trees commence growing in spring, 

 when they commence feeding on the young snoots. 

 During J une they gnaw their way into the shoots, change 

 into the pupa stage, and rest till July. The moth is 

 rather larger than the Pine-bud Tortrix Moth, and reddish- 

 yellow, with silvery spots and wavy lines across the 

 tore-wings. 



All shoots that are observed to be curved during J une, 

 or turning brown, should be carefully removed, without 

 injury to the rest, dropped in a pail or other close vessel, 

 and burned to prevent the moths reaching the perfect 

 state in July. Future attack will thus be lessened or 



prevented in proportion to the care with which the 

 injured shoots are collected. 



REITNIPHY LLUM. (From retine, resin, and phullon, 

 a leaf. Nat. ord. Rubiads [Rubiacea?]. Linn. $-Pen- 

 tandria, i-Monogynia. Allied to Hamiltonia.) 



Stove evergreen shrub. Cuttings of half-ripened 

 shoots in sand, under a bell-glass, and iu a sweet, moist 

 bottom-heat ; sandy loam and fibrous peat, with pieces 

 of charcoal. Winter temp., 55 to 60 : sunn 

 to 85. 



R. secitndiflo'rum (side-flowering). 10. White. Vene- 

 zuela. 1839. 



RETINO'SPORA. (From refine, resin, and spora, seed, 

 offspring. Nat. ord. Coniferae. The proper spelling 

 should have been Retini' spora. Now referred to 

 Cupressus.) 

 R. du'bia (doubtful). See THUYA OCCIDENTALS ERI- 



COIDES. 



ellwangeria'na (Ellwangerian). See THUYA OCCIDEN- 



TALIS ELLWANGERIANA. 



juniperoi'des (juniper-like). See THUYA ORIENTALIS 



DECUSSATA. 



leptocla'da (slender-branched). See CUPRESSUS 



THYOIDES LEPTOCLADA. 



obtu'sa (blunt). See CUPRESSUS OBTUSA. 



Cri'ppsii (Cripps's). See CUPRESSUS OBTUSA 



CRIPPSII. 

 lycopodioi'des (lycopod-like). See CUPRESSUS 



OBTUSA LYCOPODIOIDES. 



,, variega'ta (variegated). See CUPRESSUS OBTUSA 



VARIEGATA. 



plumo'sa (feathery). See CUPRESSUS PISIFERA 



PLUMOSA. 



Sande'ri (Sander's). Twigs sea-green. A provisional 



name. Also named Juniperus Sanderi. 1899. 

 squarro'sa (spreading). See CUPRESSUS PISIKERA 



SQUARROSA. 



RHABDOTHA'MNUS. (From rhabdos, a rod or wand, 

 and thamnos, a shrub ; in allusion to the twiggy branches. 

 Nat. ord. Gesneraceae.) 



Half-hardy or greenhouse shrub. Cuttings in sand 

 under a bell-glass. Loam, leaf-mould, or peat and saad. 

 R. Sola'ndri (Solander's). 2-4. Orange, striped with 

 brown. New Zealand. 1903. 



RHA'MNUS. Buckthorn. (From rham, a Celtic 

 word, signifying a tuft of branches, or the Greek, rhamnos, 

 a thorn-bush. Nat. ord. Rhamnads [Rhamnaceae]. 

 Linn. s-Pentandria, i-Moiwgynia.) 



Greenhouse and stove species, by cuttings in sand, 

 under a glass, in summer, and in a cold or close, warm 

 pit respectively ; sandy loam and leaf-mould. Hardy 

 species, by seeds, layers, and cuttings, and more especially 

 the latter mode with all the evergreens, which should be 

 taken off in the autumn, and inserted in sandy soil, in 

 a shady border, with hand-lights over them ; good 

 garden-soil. 



GREENHOUSE EVERGREEN SHRUBS. 

 R. amygdali'na, (almond-like). See R. OLEOIDES. 

 celiifo'lia (Celtis- leaved). 20. Green, yellow. May. 



S. Africa. 

 crenula'ta (scolloped). 8. Green, yellow. April. 



Teneriffe. 1778. 

 cro'ceus (saffron). 4. Green, yellow. North-western 



Amer. 1848. 

 integrifo'lia. (entire-leaved). 3- Green. Teneriffe. 



1822. 

 prinoi'des (winter-berry-like). 10. Yellow. June. 



S. Africa. 1778. 



Utrago'na (four-angled). See CASSINE SCANDENS. 

 Ihee'zans (Theezan). See SAGERETIA THEEZANS. 



STOVE EVERGREEN SHRUBS. 

 R. spharospe'rma (spherical-seeded). 15. Green, yellow. 



W. Ind. 1824. 



suriname'nsis (Surinam), i. Green, yellow. Guiana. 

 1820. 



HARDY DECIDUOUS SHRUBS. 

 R. alnifo'lia (alder-leaved). 4. Green. May. N. Amer. 



1778. 

 alpi'na (alpine). 3. Green. May. Switzerland. 1572. 



3 A 



