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CHAP. XIII. OF THE HARDY LIGNEOUS PLANTS OF THE ORDER POLYGONA CEÆ.
DISTINCTIVE Characteristics. Leaves alternate. A filmy cylindrical sheath, called an ochrea (which signifies a boot), arises from the base of every leaf, except in three genera, and surrounds the stem or branch for more or less of the interval between that leaf and the next above it. Generally speaking, this is sufficient to distinguish the Polygonaceæ from all other plants. Additionally, they have an erect ovule, with a superior radicle, and, in most, farinaceous albumen. (Lindley Nat. Syst. of Bot.) The hardy ligneous species are included in the three genera, Tragopyrum Bieb., Atrapháxis L., and Calligonuin L.; which have the following characters. Tragopy'RUM Bieb. Calyx inferior, with 5 sepals, that are imbricate in
æstivation, permanent; the 2 exterior smaller, the 3 interior investing the fruit, which is an achenium that is 3-cornered in a transverse section of it. Stamens 8. Styles 3. Undershrubs, with the habit of Atrapháxis, but decumbent or trailing; and the leaves of one of the species, at least (T. buxifòlium Bieb.), are deciduous. In the stamens and pistil they resemble Polygonum, and in the calyx Rùmex. (Bieb. Fl. Taur-Cauc., iii. p. 284. ; Lindley Nat. Syst. of Bot.; and observation.) Pedicels jointed in T. lanceo
làtum Bieb. and T. polygamum Spr. (Vent.) Atrapha'xis L. Calyx inferior, of 4 leaves, in an outer smaller pair and an
interior pair, the latter resembling petals; or 4-parted, with the lobes equal. Stamens 6. Stigmas 2, in one species ; style bifid, in the other. Fruit compressed, in one species; roundish, in the other. Seed 1. Species 2. Small shrubs, with leaves more or less ovate. (Willd. Sp. Pl., 2. p. 248,
249., and obs.) CALLIGONUM L. Calyx inferior, persistent, turbinate in the lower part,
ending upwards in a 5-parted spreading border; the 2 outer lobes rather the smaller. Stamens about 16; the filaments slightly united at the base, and then diverging. Anthers peltate. Germen 4-sided, acuminate. Styles 4 or 3, united at the base for a little way, slender, spreading. Stigmas capitate. Fruit an achenium that has 4 sides and 4 wings; and the wings are either membranous, longitudinally 2-parted, toothed, and curled, or rough with branched bristles. C. Pallàsi, the best-known species, is an erect shrub 3 ft. or 4 ft. high, with rush-like shoots, without obvious leaves, with the flowers in groups, and their calyxes partly white. (L'Héritier in Lin. Soc. Trans., i. p. 177.; and Rees's Cyclop:)
TRAGOPY'RUM Bieb. The Goat Wheat. Lin. Syst. Octándria
Trigynia. Identification. Bieb. Flor, Taurico-Caucas., 3. p. 284. Synonyme. Polygonum Lin. Hort. Ups., 95., Willd. Sp., 2. p. 440., Bot. Mag., t. 1055., Bot. Reg.
t. 055. Derivation. Tragos, a goat, and puros, wheat. The s-cornered fruits of such of the Polygonaceæ
as have them are comparable, with some allowance, to wheat; and goats may feed upon those of the Tragopýrum, or upon the shrubs themselves; or it may be that the name has been invented as one readily distinctive from the name Fagopýrum, now the name of a genus that includes the different kinds of buck-wheat.
hat 1. T. LANCEOLA'Tum Bicb. The lanceolate-leaved Goat Wheat. Identification. Beb. Fl. Taurico-Caucas. Synonymes. Polygonum frutéscens Willd. Sp. Pl., 2. p. 440., Willd. Baumz., p. 286., Bot. Reg.,
t. 258. ; strauchartiger Knöterig, Ger.
Spec. Char., &c. Stem spreading widely.
Leaves lanceolate, tapered to both ends, flat. Ochrea lanceolate, shorter than the internode. The 2 exterior sepals reflexed, the 3 interior ones obcordate. Flowers octandrous, trigynous. A native of Siberia and Dahuria. (Willd.) A shrub, a native of Siberia, growing from 1 ft. to more than 2 ft. high, branchy, even to the base. Introduced in 1770, but rare in collections. Branches twiggy. Leaf with a frosty hue, spathulate-lanceolate, nearly 1 in. long, several times longer than broad; its edge obscurely indented. The petiole short. The ochrea ends in 2 acuminate points. The flowers are borne on terminal twigs, are pediceled, erect, axillary, 1–3
1161 in an axil, often 3, and are so disposed as to constitute leafy racemes. The calyxes are whitish, variegated with rose colour, and persistent; and of the 5 sepals to each flower, the 3 that invest the ovary after the flowering become more entirely rosy. The pedicels, erect while bearing the flower, after the flowering become deflexed, and render the fruit pendulous. (Bot. Reg.) There is a plant in the Horticultural Society's Garden, in an unfavourable situation, being much shaded by trees, which is upward of 1 ft. in height; and there is one in the arboretum of Messrs. Loddiges, which forms a hemispherical bush 24 ft. high; which, during great part of July and August, 1836, was covered with its beautiful white flowers, tinged with pink; and formed a truly admirable object. It thrives best in peat soil, and is worthy of a prominent place in the most select collections.
* 2. T. BUXIFO‘LIUM Bieb. The Box-leaved Goat Wheat. Identification. Bieb. Fl. Taurico-Caucas. Synonymes. Polygonum crispulum var. e Sims Bot. Mag., t. 1065. ; P. caucásicum Hoffmannsegg. Engravings. Bot. Mag., t. 1065.; and our fig. 1162. Spec. Char., 8c. Leaf obovate, obtuse, tipped with a short
1162 mucro; the lateral margins undulated and reflexed, glabrous. Ochreas with 2 awns. (Sims in Bot. Mag, t. 1065.) A shrub, a native of Siberia. Introduced in 1800, and flowering in July. Its decumbent branches will extend 2 ft. and upwards on every side of the root; their bark is ash-coloured. The leaves are of a light green colour, rather rounded in outline, about 1 in. in diameter, and deciduous. The flowers are produced in long racemes, are nodding, and white. The fruit is enclosed by the 3 inner sepals, which become, as the fruit ripens, of a rosy colour. This, and the preceding species, are extremely interesting and beautiful little shrubs, and it is much to be regretted that they are so very seldom seen in collections. Though they require heath soil, and some little time to be firmly established, yet when once they are so, from their compact neat habit of growth, very little care will be necessary afterwards. They never can require much pruning, are quite hardy; and, provided the soil be not allowed to get too dry in the heat of summer, they are always certain of flowering freely. We hope in due time to see our provincial horticultural societies encouraging the growth of plants of this kind, by offering preiniums for well grown specimens; and for those who collect the greatest number of sorts.
# 3. T. POLY'GAMUM Spr. The polygamous-sexed Goat Wheat.
Spec. Char., &c. Leaves spathulate-linear. Ochreas lanceolate, shorter than the internodes. Flowers in branched racemes, whose rachises are thread.shaped: Styles distinct. A native of dry sandy wastes in Carolina. Introduced in 1810, and flowers in July and August. (Spreng.) T. polygamum Spr. differs from T. lanceolatum Bieb., especially in the following points : stem very much branched; leaf spathulate; sexes polygamous; sepals expanded during the Aowering; and ochreas entire at the top. The polygamous condition of the sexes consists in the flowers of the same plant being some bi. sexual, some female. (Vent. It is a shrub less than 1 ft. high. Its stem is upright, of the thickness of a raven's quill, cylindrical, and bears in its upper part numerous slender ramified branches, that are disposed so as to form a bushy head. The stem, branches, and branchlets are of a brown colour, and all bear ochreas of this colour, and that are striated, membranous at the tip, truncate on one side, and end lanceolately on the other. The leaves are spathulate, reflexed, glabrous, less than half an inch long, a fourth of their length broad, and
1163 of a delicate green colour. The flowers are small, of a greenish white colour, disposed in racemes that are axillary and terminal; and they together give the appearance of a globose panicle. The rachis of the raceme bears ochreas. The pedicels have each a joint. (Vent. Cels.) We have not seen the plant.“ In fig. 1163. a is a stamen, 6 the pistil, and c the bisexual flower.
T. pungens Bieb., T. glaucum Spr., T. grandiflorum Bieb., are de. scribed by botanists, but not yet introduced.
ATRAPHA'XIS L. The ATRAPHAXIS. Lin. Syst. Hexándria Digýnia. Identification. Schreb. Lin. Gen., No. 612. ; Willd. Sp. Pl., 2. p. 248. Derivation. According to some from a privative, and trepho, to nourish; in allusion to the fruit,
which, though in form like that of the buck wheat, is unfit for food; according to others, para to athroos aurein, from its coming up quickly from seed, viz. on the eighth day.
* 1. A. spino'sa L. The spine-branched Atraphaxis. Identification. • Lin. Hort. Cliff., 138. ; Mill. Dict., No. 1. ; L'Hérit. Stirp. Nov., 1. p. 27. t. 14. ; Willd.
Sp. Pl., 2. p. 248. ; Wats. Dend. Brit., t. 119.
Tourn. Cor., 83.
Dend. Brit., t. 119.; and our fig. 1164.
distinguishes it from the other species, A. undulata, and is implied in the epithet spinosa. In the following description, most of its characters are noted :- A shrub, of about 2 ft. high, upright, with
1164 most of the branches directed upwards, but with some horizontal, and some a little deflexed. The horizontal and deflexed ones are the shorter, and, when leaflens, have the appearance of spines. Watson has attributed (Dend. Brit.) this to their tips being dead: and the case seems to be so. The bark of the year is whitish; that of older parts is brown. The foliage is glaucous. The flowers are white. The leaves are about half an inch long, many less. The disk ovate-acute; the petiole short. The flowers are borne a few together about the tips of shoots of the year ; each is situate upon a slender pedicel, that has a joint about or below the middle, and arises from the axil of a bractea. The calyx is of 4 leaves that are imbricate in æstivation. The 2 exterior are smaller, opposite, and become reAlexed. The 2 interior are opposite, petal-like, horizontal during the flowering, afterwards approximate to the ovary, which is flat, and has one of the approximate sepals against each of its flat sides. Stigmas 2, capitate. Stamens connate at the se, into a short disk that surrounds the base of the ovary. (Observation, and Willd. Sp. Pl., and Wats. Dend. Brit.) Indigenous near the Caspian Sea, and in the Levant, and flowering in August. It was introduced in 1732, but is rare in collections. There is a fine plant in the arboretum of Messrs.
Loddiges, upwards of 2 ft. high, which was profusely covered with white flowers, tinged with pink, in August, 1836. It frequently ripens seeds there; but no plants have hitherto been raised from them. There is also a plant in the Chelsea Botanic Garden. It thrives best in sandy peat, and is propagated by layers. So elegant and rare a plant deserves a place in every choice collection.
22. A. UNDULA'TA L. The waved-leaved Atraphaxis. Identification Lin. Hort. Cliff., 137.; Willd. Sp. Pl., 2. p. 249. Engraving. Dill. Elth., t. 32. f. 36. Spec. Char., &c. It is less rigid than the A. spindsa, and has not a spiny character. Its leaves are ovate, waved at the edges, and of a greener bue. The calyx is 4-parted, and has the lobes equal, ovate, and concave. Stamens lanceolate. Style bifid. Fruit roundish. (Observation, and Wiud. Sp. Pl.) A native of the Cape of Good Hope, whence it was introduced in 1732, but rare in collections. In British green houses, it flowers in June and July; and, when planted out in the open garden, it will produce
shoots from subterraneous stolones. We have not seen the plant.
CALLIGONUM L. THE CALLIGONUM. Lin. Syst. Dodecándria Tetra
gynia. Identification. Lin. Gen., 680. ; L'Héritier in Lin. Soc. Trans., 1. p. 177. ; Willd. Sp. Pl., 2. p. 926. Synonymes. Pallàsia L., Pterococcus Pall Derivation. Kallos, beauty, gonu, a knee; in description of the neat and jointed character of the branches.
# 1. C. Palla'sia L'Herit. Pallas's Calligonum. Identification. L'Hérit
. Stirp., 2. p. 37., and in Lin. Soc. Trans., 1. p. 177. ; Ait. Hort. Kew., 2. p. 212.; Willd. Sp. Pl., 2. p. 927. Synonymes. Pterococcus aphyllus Pall. Voy., 2. p. 738. t. 8.; Calligonum polygonöldes Pall. Itin., 3. p. 536i. ; Pallàsia caspica Lin. fil. Suppl., 252., Savigny in Encyc.; Pallàsia Pterococcus Pall. FZ Ross., 2. p. 70. t. 77, 78. ; Caspischer Hackenknopf,
Ger. Engravings. Lam. In., 410.; Pall. Itin., 2. t. 81.; Pall. Fl. Ross., 2. t. 77, 78.; and our figs. 1165, 1166. Spec. Char., &c. Fruit winged : wings membranous, curled, and toothed. (L'Hérit. in Lin. Soc.
Trans.) Ashruh, 3nt, or 4 ft. high. Introduced in 1780, but rare in collections. In its native state, on the banks of the Caspian Sea, its root is thick, woody, 11 in. in diameter, striking deep into the sand, with a tuberose head. Sterns numerous, about the thickness of a finger, erect, branched, spreading, dichotomous, brittle, with a grey striated bark.' Branches alternate, round, zigzag, pointed, a little knotty; without 1165
leaves ; putting out every spring, at each
joint, from 6 to 10 close-set, herbaceous,
rush-like shoots, sometimes simple, some-
solitary, at each joint of the herbaceous shoots; round, awl-shaped, fleshy, resembling the shoots ; half an inch long. Pallas says there are no leaves; but L'Héritier affirms they were actually present in plants cultivated by himself, which were bearing flowers and fruit. Flowers numerous, in clusters, 35 in a cluster, lateral, or axillary within
1166 the stipules, on the young or woody branches, as well as on the herbaceous shoots ; white, with a greenish tinge in the middle. Stamens 16, the length of the calyx, and withering with it as the fruit increases, without falling off. Filaments bristle-shaped, thickest at the base, downy. Anthers nearly globular, 2-celled. Ovary conical, 4-sided, rarely 3-sided, the bifid angles prolonged so as to form the wings of the fruit. Wings somewhat oval, of a crimson colour, striated, and split on the edges, spreading on each side so as to conceal the nut. Pallas describes this plant as a singular shrub, growing plentifully in the Desert of Naryn, and in the sandy tracts between the rivers Rhymnus and Wolga, lying towards the Caspian Sea, where it frequently covers whole hills; the branches attaining the height of a man, and the roots often descending upwards of 6 ft. into the sand. It abounds on gravelly hills near the Wolga, at Astracan, and near the mouths of the Cama, in the deserts of Tartary. The thick part of the root being cut across in the winter season, a gum exudes, having the appearance of tragacanth. Infused in water, it swells, and is changed into a sweetish mucilage, which does not soon grow dry; and, if exposed to heat, ferments in a few days, and acquires a vinous flavour. The wandering tribes form tobacco pipes and spoons from the knots found upon the trunk. The smoke of the wood is said to be good for sore eyes. The fruit is succulent, acid, and excellent for quenching thirst. The flowers are produced in May, and the fruit ripens in July. The nuts germinate freely when sown deeply in sand, and the two seed.leaves break forth, and suddenly spring up, in one night, 1 in. in length, and thread-like and decumbent; but they become speedily erect.
C. comosum L'Hérit. In Lin. Trans., 1. p. 180., Willd. Sp. Pl., 2. p. 927.; and C. Panderi L'Hérit. ; are described by botanists, and registered in Sweet's Hortus Britannicus as introduced ; but we are not aware of their being in the country.
App. I. Half-hardy Species of Polygonacee. Brunnichia cirrhòsa Gærtn. Fruct., 1. t. 45. f. 2., is a tendriled climber, a native of Carolina, with alternate, cordate, acuminate leaves, and flowers in panicled racemes. It was introduced in 1787, and is occasionally met with in old collections ; for example, in the Cambridge Botanic Garden.
Rümer Lunària L., Pluk. Alm., 252, 253., is a native of the Canaries, with roundish glaucous leaves, which has been occasionally found in green-houses, since the days of Parkinson. It grows to the height of 5 ft. or 6 ft. in the Cambridge Botanic Garden; and produces its greenish flowers in June and July. There are two other African suffruticose species recorded in our Hortus Britannicus ; and there is a plant in the Horticultural Society's Garden, from Moldavia, which has twining stems, and of which a portion is represented in fig. 1167. It grows against a wall with an east aspect, and, though frequently killed down during winter, never fails to spring up vigorously the following spring.
Polygonum adpressum R. Br., Bot. Mag., t. 3145., the Macquarrie Harbour vine, is a native of Van Diemen's Land, principally on the sea shore, about Macquarrie Harbour. It is an evergreen climber or trailer, growing to the height of 60 ft.; flowering from May to August ; and ripening its fruit in December and January. The flowers are axillary, and are succeeded by racemes of fruit, which, at first sight, resemble grapes. “The seed of all the polygonums, which is a small hard nut, is known to be wholesome, (buck-wheat, for example); but in P. adpressum the seed is invested with the enlarged and fleshy segments of the calyx, which gives to each fruit the appearance of a berry : some acidity in this fruit renders it available for tarts.” (Bot. Mag:, April, 1832 ; see also Gard. Mag., vol. viii. p. 347., and vol. xi. p. 341.) This plant was introduced in 1822 ; and, though considered as requiring the green-house, yet we have little doubt it would live against a conservative wall, or as a trailer on dry rockwork, in peat soil, in a warm situation. The extraordinary rapidity of its growth might perhaps recom. mend it for the same purposes as the coboa, and other rapid-growing climbers.
OF THE HARDY AND HALF-HARDY LIGNEOUS PLANTS OF THE ORDER
This order is distinguished from all others by the following short characteristics :- Anthers opening by valves which curve upwards ; carpels solitary and superior; and ovules pendulous. (Lindl. Nat. Syst. of Bot.) The only other order treated of in our work, in which there is an analogous mode of opening in the anthers, is Berberàceæ. The species are chiefly trees, some of them shrubs, natives of Asia and North America, and one of them of the south of Europe.
LAU'RUS Plin. The Laurel, or BAY, Tree. Lin. Syst, Enneandria
Monogynia. Identification. Pliny, on the authority of C. G. Nees von Esenbeck in Lindl. Nat. Syst. of Bot,
p. 02. ; Lin. Gen., No. 503., in part, and so of most other botanical authors. Synonymes. Sassafras and Benzdin, C. G. Von Esenbeck; Daphne, Greck. Derivation. From laus, praise; in reference to the ancient custom of crowning the Roman con
querors with laurel in their triumphal processions. There appears some doubt of the Laurus nobilis being the Laurus of the Romans, and the Daphnē of the Greeks. (See Dáphne.) As, however, nothing certain is known of the subject, we have followed the popular belief; and, in the history given below of the Laurus nobilis, we have treated it as if identical with the Daphně of the Greeks. Gen. Char., fc. Sexes polygamous, or diæcious. Calyx with 6 sepals. Stamens 9;
6 exterior, 3 interior, and each of them having a pair of gland-like bodies