ground as in the Orcuts. (2) Fleshy tubercles, having a bud at their extremities containing amylaceous granules for the nutrition of the plant. (3) Fleshy branching bodies of tortuous and

of Orchidaceous Flowers. Fig. 359.—Forms angular form, as in Neottia, or resembling tubers, as in Gastrodia- og (4) Simple or branched shoots, capable of extension, protruding from the stem into the air, and formed of a woody and vascular | axis, covered with cellular tissue, the subcutaneous layer gti a cells, the points ° Ae of large reticulated often green, and composed the roots being usually green, but sometimes red or yellow. » where it isonly# state in Ophrydee, The stem is in its simplest

Fig. 359.—Forms of Orchidaceous Flowers.

growing point surrounded by scales, and constituting a leaf-bud when at rest, which eventually grows into a sccondary stem or branch in which leaves and flowers are developed. This kind of stem develops every year a lateral bud with a tubercular root attached, which, after unfolding its flowers-and ripening its fruit, perishes, to be succeeded by the stem belonging to the lateral bud; hence the species having this kind of stem has always a pair of tubercles attached, one shrivelling and in process of exhaustion, the other swelling and progressing towards completion. The leaves are uncertain,—usually they are sheathing at the base, and membranous; but in Vanilla they are hard, stalked, articulated at the base, and have no trace of a sheath. Sometimes they are leathery and veinless, frequently they are membranous and strongly ribbed, especially in Maxillaria and Cypripedium. “The floral envelopes are constructed upon a ternary type, and consist of three exterior and three interior pieces, the exterior ing nearly equal, but less brilliantly coloured than the interior, but the two lateral ones are often of a somewhat different form from the other, which is anterior when young, but becomes posterior when the flower expands, in consequence of the flower-stalk ming twisted or curved. “The centre of the flower is occupied by a body called the Colusan, which is formed by consolidation of style and stamens, of which there are, in the greater part of the order, only one present, which igs placed opposite the intermediate sepal, and, consequently, alternate with the petals, but in Cypripedium there are two sta- Mens. In the greater part of the order a single anther terminates thecolumn. This is usually two-celled, but often has its cells divided Into two or four other cavities by the extension of the Endothecium between the lobes of the pollen-masses, or it is occasionally More or less completely one-celled by the absorption of the con- | nective,” . The pollen consists of lenticular or spheroidal grains, either — Single or cohering in pairs, threes, or fours, or in larger masses in indefinite numbers; usually held together by an elastic filamentous _ _ Stance, which either contracts on adhesion with a gland origi- 2 Rating on the margin of the stigma, as in Ophrydea, Neottiew, - Vandee, or it is folded — the pollen-masses, as in x

Epipendree or it terminates in an amorphous dilatation, as in many Malaxidee. ese differences in the structure of the column, anther, and pollen, furnish botanists with the best means of classifying the order and breaking it into sub-orders, thus:—

izHaving the anthers free, opercular, or) vered with a lid, pollen-masses waxy, thallis. Li

I. MALAXIDE. with neither caudiculanor gland; roots Re ba gh aa a thick and fleshy +bcpcrmys see bulbous in Liparis and Malax

Anther aca, pollen waxy, svand no Including Epidendrum, Celo-

Il. EPIDENDREX, |tide back upon the pollen grains, and no gyne, Leelia, and Bletia.

Including Vaunda, Sarcanthus,

Ill. VANDE#. {saneAnther opercular,audiculapollenand giand sia,a Oncidium, bein with a aie pbgion

Anther erect, with distinct Ragone \ {raitenscople or granular, form renarage ie gale se IV. OPHRYDES. round which the masses of gp od gor nadenis, thrix, Disa,

| arranged, sometimes fforming a strap or Corycium

\ caudicula. ) her opercular, pollen granularo! Including Limodorum, Acian- = nthe V. ARETHUSEZ. {acs iplip slightly articulated with th thus, cometFogle, Gastrodia some “ eros and dorsal, having the) 1, has Cranichis, Lister stigma in ang Bers powdery, having the Spiranthes, Physurus,

VI. Neorrinz. fut adherentto a gland on the margin pike ti toe of stigma, ee eT ioAnthers two, separated by a broad viget Including Cypripedium only.

Among the Mataxtne® we find many British species, as the coral-rooted Corallorhiza erimata, whose root gives out the scent of the vanilla when drying; Liparis loveselli, with its yellowish ten-flowered spike;but the more beautiful species, of this sub-order are found among the Dendrobiums, an extensive genus of East ‘Indian Epiphytes found in the moister parts of Asia, of tropical Japan and Australia. Q Orchids. The Vanpzm have no representative among British Orchidaceous to all given originally a name The Epidendrums, piphytes, are now restricted to a genus of the order having the cPaeMnSSpSeeenea lebethien united to the column, and four pollen-masses ere: as many little straps bent back upon them; a group containing — some showy and interesting plants, but many of them inconspicuovs and unimportant. Among the other genera, however, som

und. The most brilliant ornaments of the conservatory are fo colours of some of the Coelogynes are rich and delicate1 we out tthrows from Nepaul, species a dwarf evergreen C. cristata, _ leaves six inches long and six or eight Areonins eo of flowae

of a delicate white with a blotch of yellow on the lip, each flower ‘being three or four inches wide. The Carriryas are, however, the most striking of all the Orchids. Their dark evergreen foliage and compact habit recommend them especially to the cultivator. The flowers are large, elegant in form, and their prevailing colours, of violet, rose, crimson, and purple, are unsurpassed for depth and brilliancy. C. granulosa, from Brazil, produces large olive-coloured flowers, with rich brown spots; the lip whitish, spotted with crimson in C. guttata. Leopoldit, another Brazilian species, grows about twenty inches high with a dark green foliage. The sepals and petals are dark brown spotted with crimson, and purple lip. Others are rose-coloured, margined with white, or sepals and petals pure white, with beautifully fringed lip of richest crimson. The Lzx1as rival, while they resemble the Cattleyas; they are compact in growth, with evergreen foliage, producing their flowers. in spikes from the top of the bulbs. In L. acuminata, from Mexico, the sepals and petals are white, and lip white with a dark blotch on the upper lip. In L. anceps the sepals and petals are rose lilae, and lip a beautiful purple, the flowers being three or four inches — ” across; others purple, with a crimson lip, or delicate rose-colour, the lip striped and shotted chocolate brown, with flowers four inches _4cross, as in L. megalis. In short, so far as graceful foliage, brilliancy of colouring, form and size of flowers are concerned, the Orchids of this division are the gems of the Vegetable World. The Vanpex include many of the most curious and interesting among Orchids, chiefly Epiphytes. The Aerides combine with their rich, evergreen, and gracefully curving stem and opposite leaves, flowers of peculiar elegance, pro- _ Ceding from the axils of the leaves, apd extending their rich and waxy petals in delicate racemes sometimes two feet in length, and yielding a most agreeable fragrance. The Acrides are natives — of the hottest parts of India and other tropical countries, attaching — themselves to trees, generally such as overhang running streams :: (Of water. 4. affine throws out its pink and white flowers in long 2S branching spikes two feetlong. A. enspwm, another Indian species, stem and dark green foliage, throws out long __ ea ‘purple-coloured Spikes of flowers of pure white tipped with pink. The Saccolabiums

closely resemble the Aerides in habit; their flowers are produce in long graceful racemes, often a foot and a half long, springing from the axils of the leaves.

Oncidium is another extensive genera belonging to the Vandew; they are chiefly natives of tropical America. The prevailing colour of their flowers is yellow spotted with rich reddish brown, and they are known by their broad labellum, more or less lobed, distinct from the column, and furnished at the base with a tuberculated disk, spreading sepals and petals, with a membranous ear on each side of the column, and two pollen-masses attached to @ long caudicula, which give the plant a grotesque resemblance to the Butterfly, the name it bears. In their native forests these Epiphytes wholly overrun the trees, clasping them round, and covering them

SreekBcos.rt°RSeRichinemveGNoceaApomeREa from top to bottom with their brilliant and grotesque flowers.

The OpHrypEx have fleshy, bulbous roots, with radical fibres, leafy stem, anther continuous with the column, and the pollen-mass agglutinated and attenuated into a pedicel. In Orchis and Gymnadenia the lip has a spur, in Ophrys it is thick and spurless, in Habenaria the spur is very long; in Aceras the outer and inner divisions converging, form a hood, lip in three linear divisions and spurless. This and the following group are natives of temperate Europe, many of them of the British Islands. so well As a representative of the family we may take the plant known in this country and in the north of France, commonly call the Flower of Pentecost, or the spotted Orchis, Orchis eae? (Fig. 360). The floral envelope of this species is composed ° in two rows he: alternately pieces, disposed_ six petal-shaped 361). Of the three exterior pieces, two are slightly lateral, eo middle one is curved forward in such a manner as to form, W! two divisions of the internal ventricle, a sort of casque oT helmet. The third division has, on*the contrary, a shape peculiar to itself; ing on the upper side it presents the appearance of a large bao ss the = apron, prolonging itself below into a sort of spur. This 18 labellum, or lower lip, of the flower. The corolla is then essentially: irregular. When the six pieces of the floral envelope are Temov”” the a central column becomes visible, having in front two cells, longitudinal openings of which face the apron. Below, an square cup, glossy and viscous, is observable. If we ope? ©”

ORCHIDACEOUS PLANTS. “Sil

cells with the point of a needle, it will be found that each of them contains a pyriform body, the upper part of which is inflated, and is composed of little angular masses, bound together by a sort of elastic network, while the lower part is lengthened into a kind of pedicel or footstalk. These two pedicels are inserted at their base in the contiguous compartments of a little pocket. If we depress one of these pynform bodies towards the cup, it adheres there firmly. We may easily satisfy ourselves that the phenomenon is spontaneously produced in nature; and that the pollen-masses are discharged upen the viscous surface from the tubes, and that they quickly penetrate its tissues. This cup, then, is the stigma, these pyriform bodies the pollen-grains, and the two cells which enclose them constitute an are united to form the f 4 /

Fig. 360.—Orchis maculats, fentral column, and it has only one stamen. Beneath the point of insertion of the floral divisions, the column

312

THE VEGETABLE WORLD.

is continued by a sort of greenish appendage, with six longitudinal ribs, much twisted when the flower is about to expand. This is the ovarium, which, as we see, is inferior. This ovarium presents one single cell, and encloses a great number of very small ovules inserted upon three placentæ attached to the internal walls of the ovary. The fruit is capsular, and opens by three valves, which bear the placentæ in their axis, whilst the midribs remain in their place, united at the base as well as at the summit. Let us now examine the organs of vegetation in the same plant. The parts which are under the ground consist of two unequal tubers (Fig. 362), one of which is wrinkled, soft, and apparently devoid of sap, whilst the other is whiter, larger, and much firmer. The substance of the first, in short, has been exhausted in the development of the aerial stem, which now bears its bunches of flowers; whilst the other is reserved for the development of the young leafy branch in the following year. These two tubers, which are ovoid or egg-shaped, are the nutritive roots. Above these roots is another little shoot, which will not be fully developed till two years later.

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