AN ENCYCLOPEDIA OF HORTICULTURE, 



301 



Rhus continued. 



America, 1640. Shrub climbing by rootlets over rocks, Ac., or 

 ascendin^ trees, poisonous to the touch. (A. F. B. iL 556 ; 

 T.-S. M. 577.) 



R. T. radicans (rooting). I. mostly entire or nearly so. Stems 

 rooting, but not climbing. (B. M. " 

 vulgare.) 



rooting, but not "climbing. (B. M". 1806, under name of R. T. 

 R. typhina (fever).* Stag's-horn Sumach; Vinegar-tree. Jt. 



t. typhina (fever).* Stag's-horn Suiuu,u , . ^..^cii-ncc. y t . 

 greenish-yellow, in a terminal, thyrsoid panicle. June. I., leaflets 

 eleven to thirty-one, pale beneath, oblong-lanceolate, pointed, 

 serrate, rarely laciniate. Branches and stalks densely-velvety 

 hairy. A. 10ft. to 30ft. North America, 1629. Shrub or tree. 

 (T. S. M. 571.) R. viridiflora (green-flowered) is a male-flowered 

 form of this species. 



R. t. arborescens (arborescent). I. slightly downy beneath. 

 A. 10ft. to 25ft. Tree. 



R. t. frutescens (shrubby). I downy and whitish beneath. 

 h. 2ft. to 10ft. Shrub. 



R. venenata (poisonous). Poison Elder, Sumach, or Dogwood. 

 }t. green, in loose and slender axillary panicles. July. I. rattier 

 glabrous than pubescent ; leaflets seven to thirteen, obovate- 

 oblong, entire. A. 6ft. to 18ft. North America. 1713. The most 

 poisonous species of the genus. (T. S. M. 575 ; W. D. B. 19.) 

 SYN. R. vernix. 



R. vernicifera (varnish-bearing). Japan Lacquer or Varnish- 

 tree. Jl. greenish-yellow. June. I. long, resembling those of 

 a Walnut ; leaflets eleven or thirteen, elliptic, acute, quite entire, 

 smoothish above, but velvety beneath from pubescence. Branch- 

 lets and stalks clothed with soft down. A. 30ft. Japan, 1823. 

 Tree. 



R. vernix (varnish). A synonym of R. venenata. 



R. villosa (villous). Jl. greenish-yellow ; racemes axillary, much 

 shorter than the leaves, the terminal ones paniculate, some- 

 what longer. July. 1. petiolate ; leaflets sessile, obovate, obtuse, 

 mucronulate, entire, lin. to liin. long, iin. to lin. wide, with 

 revolute margins, hairy or villous on both surfaces, as well as the 

 petioles and branchlets. Cape of Good Hope, 1714. Greenhouse 

 evergreen shrub or tree. SYN. R. atomaria. 



RHYXCHADENIA. A synonym of Macradeiiia 

 (which see). 



RHYNCHANTHERA (from rhynchos, a beak, and 

 anthera, an anther; the anthers are beaked). OBD. 

 Melastomacece. A genus of about two dozen species 

 of glandular or pilose, often bristly, stove, annual 

 or perennial herbs or shrubs, natives of Brazil, Guiana, 

 New Grenada, and Peru. Flowers purple, panicled, 

 often large, showy ; calyx tube ovoid OY campanu- 

 late ; lobes five, subulate, lanceolate, or bristly, often 

 persistent; petals obovate; stamens ten, very unequal. 

 Leaves ovate, cordate, or oblong. The only species in- 

 troduced R. grandijlora is a handsome, stove, evergreen 

 shrub. It requires a compost of rich, sandy peat and 

 fibry loam. Ample drainage is essential. Propagation 

 may be effected by cuttings, inserted in sandy loam, in 

 heat, and covered with a bell glass, which should be 

 slightly raised, in order to permit free circulation, and, 

 at the same time, to prevent damping off. 

 R, grandiflora (large-flowered), fl. numerous, terminal, shortly 

 pedicellate ; calyx tube purple, shorter than the narrow teeth, 

 panicle dichotomously branched, corymbiform. Autumn. L. 

 rather large and long-stalked, cordate-ovate, shortly acuminate, 

 serrulated, seven to nine-nerved, slightly bristly. Branches sub- 

 terete, hairy, or sometimes slightly hispid. A. 6ft North Brazil, 

 1873. (B. M. 6011.) 



RHYNCHITES. A genus of Weevils, noteworthy 

 for the harm done by several of the species to trees. 

 Some of them have the habit of rolling part of a leaf, 

 or one or more leaves, into a cone, to supply protection 

 and food to the larvae. The cones hang in a withered 

 state by the half-cut stalks or midribs of the leaves. 

 Others gnaw partly through young shoots, or young 

 fruit, and lay one or more eggs in each, and the larvae 

 feed in the withered branch or fruit. By the time the 

 larva is full-fed, the part of the plant containing it 

 has usually fallen off, and the larva crawls into the earth, 

 there becomes a pupa, and, finally, the beetle emerges, 

 generally in the following spring. The beetles are harm- 

 ful also by gnawing the young leaves and branches 

 of most kinds of trees, including fruit-trees, for their 

 own food. They are all small, usually being from iin. 

 to iin. long. The general outline is broadly pear- 



Rhynchites continued. 



shaped, the wing-cases being rather square in front, and 

 broader than the thorax. The head bears a rather long, 

 decurved beak, on the middle of which are the straight, 

 clubbed antennae. The beetles are all shining dark blue, 

 green, brown, or coppery-red in colour. Reference has 

 already been made to these insects as injurious to Pear- 

 trees, Plum-trees, &c. The following are the most 

 hurtful species : 



R. Alliance is much like R. conicus in size and colour, 

 but the thorax is finely pitted, and has a smooth dorsal 

 line, and the elytra are not decidedly wider behind the 

 middle. The larvae live in the stalks and midribs of the 

 leaves of many fruit-trees, e.g., Apple, &c. 



R. Bacchus is iin. to ^in. long, purple-red, with a 

 golden-coppery gleam on the wing-cases and on the back 

 of the neck ; beak, legs, and antennae are blue- black ; 

 wing-cases deeply punctured, and transversely wrinkled. 

 This species prefers Apple and Pear trees, but is not 

 restricted to them. The larvae live in the still unripe 

 fruits, which are hindered and interfered with in their 

 growth. 



R. betuleti is about -^in. long, or more, entirely blue 

 or shining green, or a combination of these, and hair- 

 less ; wing-cases closely punctate, irregularly striate, not 

 wrinkled. The beetles live on many kinds of tree.-*, but 

 prefer, among those of gardens, Pear-trees and Vines. 

 The females make conical habitations for the larvae out 

 of one or several leaves rolled together, and caused to 

 wither by their stalks being partly gnawed through, as 

 stated above. 



jR. conicus is from fin. to in. long; colour deep blue, 

 sometimes with a greenish tinge; beak and limbs black; 

 thorax coarsely pitted ; wing-cases deeply punctate- 

 striate, broadest behind the middle. In May and June, 

 the females lay eggs in the young shoots of Apples, 

 Pears, Plums, Cherries, and other fruit-trees, and then 

 gnaw the branches partly through below the situation 

 of the eggs. The branches fade and hang down, and 

 in this state form the proper food of the larvae, which 

 feed in the pith. 



R. cupreus is about in. or iin. long, and is coppery 

 or bronze-coloured, with a thin coat of greyish hairs ; 

 the beak and limbs are black; the thorax is closely 

 punctured; the elytra are deeply punctate-striate, with 

 the interspaces transversely wrinkled. The beetles live 

 on all kinds of fruit-trees in early summer, and do con- 

 siderable harm by gnawing the young shoots and buds; 

 but they prefer Cherries and Plums. The females seek 

 out the young fruits, and deposit an egg in a hole bored 

 in each, after the stalk is gnawed half through, so that, 

 after a time, the fruits fall to the earth. The larvae 

 feed in the fruits till ready to enter the soil, there to 

 become pupae. 



A beetle of this genus, R. bicolor, injures Roses in the 

 United States. 



Remedies. These consist of the capture of the beetles 

 by shaking the trees over trays tarred inside, and the 

 removal of the conspicuously injured leaves, young 

 branches, or fruits, to be burned as soon as convenient. 

 Fortunately, the evil can be checked, in most cases, 

 without serious labour. 



RHYNCHOGLOSSUM (from rhynchos, a beak, and 

 glossa, a tongue ; the lower lip of the flower is in the 

 form of a tongue-like beak). STNS. Antonia, Loxotis. 

 OBD. Gesneracece. A genus of one or two species of 

 closely - related, erect, slightly - branched stove herbs, 

 broadly dispersed over the East Indies and the Malayan 

 Archipelago. Flowers blue, rather large, shortly pedi- 

 cellate, pendulous; calyx broadly tubular-campanulate, 

 shortly five-fid; corolla tube cylindrical, loosely incurved; 

 limb bilabiate, the dorsal lobe shortly bifid, the anterior 

 one much larger and trifid, the lateral ones shorter ; 



