Illustrations of Indian Botany, Vol. 1/Dilleniaciae
DILLENIACIAE.
In this order the calyx is 5 sepaled, hypogynous, and persistent ; three of the sepals exterior and two interior : the corolla 5 petaled, deciduous, the stamens numerous, usually, all distinct and free, but sometimes monadelphous or polyadelphous, placed either all round the pistils in the usual way, or confined to one side of it: filaments, when free, dilated at either the base or apex: anthers adnate 2 celled, either elongated and bursting longitudinally, or short with the cells united at the tip only, and placed transversely across the dilated point of the filament. Pistils definite in number, ovaries, usually, from 3 to 5, but sometimes numerous, rarely solitary, more or less united, and terminated each by a straight style and truncated or toothed stigma; ovules, frequently numerous, sometimes reduced to two, or even one, pendulous or erect. Fruit composed of as many one-celled carpels as there were ovaries, either altogether distinct, or more or less cohering. Seeds usually, by abortion, few or solitary, attached in a double row to the inner edge of the carpels, and surrounded by a pulpy arillus; the testa hard, embryo minute, lying at the base of a fleshy albumen.
Handsome flowering trees or shrubs, are the most prevalent forms in this order, some of the former affording excellent timber, the latter usually climbing or prostrate, a few herbaceous plants are also met with. The leaves are usually alternate, and exstipulate, coriacious, with strong veins running straight from the midrib to the margin; peduncles solitary, or several springing together from tubercles on the branches, or forming terminal racemes or panicles. Flowers often yellow.
Affinities. The affinity existing between Dilleniaceae and Ranunculaceae has been already adverted to; they are also nearly akin to Magnoliaceae, from which they are distinguished by the absence of stipules, (Wormia excepted) by their persistent calyx and stamens, and lastly, by the quinary arrangement of their parts of fructification, the petals forming a single, not several, series. They are universally distinguished by the presence of an aril to the seed, and generally by the peculiar venation of the leaves; the veins running straight from the midrib to the margin, and frequently projecting in form of a tooth. The very remarkable one-sided development of the stamens, in some of the genera, is peculiar to this order.
From Anonaceae they are separated by nearly the same characters as those which separate them from Magnoliaceae, namely, the persistent calyx and quinary arrangement of the floral envelopes ; but in both, the leaves are exstipulate.
Essential Character. Flowers polypetalous, polyandrous, ovaries wholly superior: carpels more or less distinct, or solitary: embryo minute: seeds with an aril, leaves exstipulate, except Wormia. Geographical Distribution. This is peculiarly a tropical order, almost as exclusively so, as Ranunculaceae is an extra-tropical one, a few only extending beyond the 30th degree of latitude. The species are natives alike of both hemispheres, most numerous in the southern. Australia may indeed be said to be the head quarters of the order, 50 species, natives of that country, being known and described by DeCandolle, when Asia and America could only boast of 21 between them, and Africa of 3 ; several however have since been added to the list, from both Asia and America, and one or two from Africa, but probably very many yet remain undiscovered in so vast a continent as Australia. Dr. Wallich has figured several new ones in his splendid Plantce Asiaticae Rariores. Blume has described eight in his additions, (Bijdragen) to the flora of Java, and there are still several undescribed species in Ceylon in addition to the one here figured. To the peninsular flora two are added, unknown when DeCandolle wrote, and it is probable more will be found when the rich forests of Malabar and the alpine valleys of the Northern Circars have been better investigated, both of which stations supply us with the same species.
Properties and Uses. Nearly every thing that is known appertaining to this order is expressed in the following brief summary. "Fine plants, almost exclusively confined to tropical countries. Dillenia speciosa a native of India, is a most noble tree, with large yellow flowers, rivalling those of a Magnolia. Hibbertia volubilis is a green house plant, well known for the beauty of its blossoms and their powerfully fetid smell. The medical properties of this order are scarcely known ; a decoction of their leaves or bark is astringent and used for gargles ; and the fruit of some of the species of Dillenia is used in India, mixed with water, as a pleasant beverage in fevers. The foliage of some of the species is extremely scabrous, whence the dried leaves are used for the same purposes as fish skin, and sand paper in Europe, those of Trachytella aspera, are even employed in China for polishing metal." Loudon's Encyclopaedia of Plants 1055.
It is certainly, to me, a matter of surprise, to find plants so fine as all the species of Dillenia are, so totally neglected in our gardens and lawns. From the facility of their culture and propagation we might expect them to be of frequent occurrence, and yet, to the best of my recollection I never saw a single species of this fine family in cultivation in India. In England where they are more attentive to the ornaments of the garden, D. speciosa is of frequent occurrence in hot houses, being prized, not less on account of the magnificence and beauty of its flowers, than for the facility of its propagation. "They thrive best in loamy soil. Ripened cuttings not deprived of their leaves, strike root freely in a pot of sand, plunged under a hand-glass in heat. Good seeds sometimes arrive from India; placed in a moderate hot-bed frame they will succeed well." Such are the brief and easily followed directions for the culture of these plants, which, I hope ere long, to see acted upon by the Horticultural Society for the diffusion of these beautiful trees among us. The species of Wormia, one of which is a native of Ceylon, are not less deserving of our attention, on account of the magnificence of their foliage and beauty of their flowers. Several species of Dillenia are large trees, and afford valuable timber on account of its hardness and durability.
As stated above, little is known regarding the properties of Dilleniacece: the leaves and bark of several are astringent, and decoctions of them are used as gargles and as washes for ill conditioned sores. The fruit of most of the species of Dillenia are acid, and used by the Natives in their curries, while the enlarged fleshy calyx of the ripe fruit, sometimes furnishes Europeans with "a tolerably pleasant jelly."
Remarks on the Genera, &c. Roxburgh, as appears from his Flora Indica, was only acquainted with nine species of this order, which he referred to two genera Tetracera and Dillenia. These nine are now distributed among four genera, his Tetracera Sarmentosa being the Delima Sarmentosa of all modern authors, and his Delenia Pentagyna having been raised to the rank of a distinct genus, though, as it appears to me, on insufficient grounds, under the name of Colbertia Coromandelina. To these four original Asiatic genera, several others have recently been added. Vahl founded Schumacheria on a Ceylon plant, DeCandolle Trachytella on one from Cochin China, Jack Acrotrema for a Malayan one, and Blume Capellia for a Javanese one, Lindley Actinidia for one from Nepaul. To these it may be added, that Wormia has been discovered in Ceylon, making up the number of Asiatic genera to 10 out of 26, the total number yet discovered.
Of these 10, four are certainly natives of the Indian Peninsula, namely, Tetracera, Dillenia, Colbertia, and Acrotrema : Colbertia however, heing only separated from Dillenia, by having a few of the stamens sterile and longer than the rest, and fewer pistils. This last character is now of no value, owing to some species recently referred to the genus, on account of their sterile stamens, having as many as 12 styles, the remaining distinction, sterile stamens, does not seem sufficient to authorize its removal as a separate genus, on which account, Dr. Arnott and myself, following Roxburgh, reunited it to the older genus, thus leaving only three for the Peninsula. Delima Sarmentosa quoted by Roxburgh as a Peninsular plant on the authority of Rheede's figure (Hort.Mal. 7 tab. 53) has not yet been found on the continent of India, Kheede's figure representing a plant not even referable to the order. The genera Acrotrema and Schumacheria, the ones here figured, require a somewhat more detailed notice. The former was established by the late Dr. Jack in the Malayan miscellanies for a Malay plant first discovered by him : since then two species have been discovered in Malabar, and some others in Ceylon. Some of the Ceylon ones I have seen, and think quite distinct from the Malabar plants, but owing to my not having specimens I do not attempt to characterize them. The genus was thus briefly defined by its discoverer, "Calyx pentaphyllus. Corolla 5-petala, patens. Stamina 15, erecta, filamentis brevibus, antheris longis, linearibus apice biporis. . Ovaria 3, distincta, 2-spora, ovulis angulo interiori affixis. Stili 3. Stigmata simplicia. Capsulae uniloculars — Herba acaulis, pilosa, pedunculis racemosa multifloris." With this character both A. costatvm and Wightianum sufficiently agree, but the species now added calls for some modifications to admit of its being received into the genus. Thus in A. Arnottianum, in place of 15 there are nearly 30 stamens, in place of 2 ovules they are very numerous, and in place of one or at most two seeds I have observed nearly 20 in one carpel. The inflorescence also differs ; for in place of a short raceme, on the extremity of an erect naked scape they are borne on a procumbent sucker-like branch, covered throughout with appressed scale-like bracts, from the axils of which, the long filiform pedicels spring.
The species equally require revision since the addition of A. Arnottianum, but that I feel averse to attempt until I receive specimens of the Ceylon species, I shall therefore content myself for the present by stating that A. costatum and A. Wightianum seem, from description, very nearly allied, if indeed distinct, (our former character is referable, partly, to two, very distinct, species, owing to our specimens of both, being so very imperfect as to prevent their being recognized as distinct) while A. Arnottianum is so widely removed from both in every thing but habit, that it may almost be considered a distinct genus. In the former, the flowers are borne on an erect scape, and the carpels 1-2 seeded; in the latter, they spring from, apparently, an abortive surculus (sucker) and the carpels are many seeded.
The genus Schumacheria was originally established by Vahl, and published in a German periodical, apparently little known, and seems to have been so imperfectly described, that DeCandolle with all his care and research, seems either to have overlooked it, or was unable to determine its affinities and place in the system of plants, as it is not taken up in his Systema Naturale. Springel has equally overlooked it, and has even published another, and very different genus, under the same name : hence we may conclude the genus was virtually lost until resuscitated by Dr. Arnott, who published a revised character in Jameson's New Philosophical Journal for April 1834. His character, though detailed and accurate, seems still to have left some point doubtful, as Professor Lindley in the second edition of his excellent "Natural system of Botany," has placed it at the conclusion of his arranged list of genera of the order, as if uncertain, either of its proper place or whether it actually belonged to the order. A genus so little known, and which may be found to merit a different fate, I have thought a suitable subject for this work. In the specific name I have followed Dr. Arnott, this being undoubtedly his plant, though it is possible, Vahl's may be a different one, as I am informed by Colonel Walker, that he has recently met with several other species, all quite distinct from the one here represented, descriptions of which I hope by and bye to have an opportunity of introducing.
Acrotrema.
Generic Character. Stamens 15-30, erect : filaments short: anthers adnate, long, linear, opening by terminal pores. Ovaries^, adherent at the base only, each terminated with a style and simple stigma: ovules few or many in each. Carpels 3, capsular: seeds 1-20, furnished with a membranous aril.
Herbaceous low plants. Leaves all radical. Petiols short, their margins dilated into membranacious, somewhat sheathing auricles. Peduncles either erect scapes, bearing a short terminal umbel-like raceme ; or sucker-like, clothed ivith dry scale-like bracts, from
the axils of which the long, slender, one-flowered peduncles, spring. DILLENIACEÆ.jpg)
ACROTREMA ARNOTTIANUM. R.W.
DILLENIACEÆ.jpg)
SCHUMACHERIA CASTANEAEFOLIA. VAHL.
1. A. Arnollianum. Leaves sprinkled with rigid hairs : peduncles, procumbent, surculose, many flowered: carpels many seeded.— Plate No. 3.
2. A. Wightianum. Leaves sprinkled with rigid hairs, more abundant on the veins: peduncles an erect scape, terminating in an 8-12 flowered raceme ; carpels, by abortion, one seeded.
Both these species are found on the Malabar Coast, the former I also found at Courtallum, where the accompanying drawing was made. They frequent moist shady places in woods, in Courtallum, and under hedges on the banks of wet ditches in Malabar, flowering July and August, perhaps also at other seasons.
SCHUMACHERIA — VAHL NOT SPRINGEL.
Sepals 5 persistent ; 2 exterior, 3 interior; estivation imbricative. Petals 5 deciduous, hypogynous, alertnating with the sepals, two with the margin crisped, estivation imbricate. Stamens hypogynous, numerous, all on one side, in several series, monadelphous, all fertile. Filaments short, united at the base into a short somewhat flattened androphore. Anthers linear, elongated, 2 celled ; mucronate at the point. Torus none. Ovaries 3, free, villous, 1 celled, 1 styled, 1 ovuled. Ovule ascending from the base, arilled. Styles simple, terminal, filiform, glabrous, during estivation incumbent on the stamens, stigmas simple.
Diffuse climbing shrubs, branches glabrous, round, purplish coloured, the young shoots somewhat flattened. Leaves alternate, coriacious, glabrous, smooth, petioled, exstipulate, repando-serrated, the serralures mucronate, feather-nerved, nerves paraded, simple. Petioles channeled, dilated at the base, half embracing the stalk. Spikes panicled, terminal, and from the axils of the extreme leaves, and equalling them in length. Flowers sessile, secund, bibracteate at the base.
S. Castaneifolia. — ( Vahl : /3 Grahamii Arnott.) Ceylon in woods near the banks of rivers. — Plate No. 4.
In the species here represented the sepals are densely clothed on both sides with appressed shining silky hairs.
Dr. Arnott distinguishes two varieties of this plant, a division which I adopt for the present but not without hesitation, as I think it probable, for the reasons already stated that Vahl's Castaneifolia and Arnott's f3 Grahamii, will be found different species. It is to me a subject of regret, that Dr. Arnott did not republish Vahl's character and description along with his own, as affording an additional means of determining, by comparing other species, known to exist, with both the old and reformed character.
EXPLANATION OF PLATES.
3d. — DlLLENIACEAE.
1. Acrotrema Arnottianum, natural size. — 2. Flower front view, and opened to show the stamens. — 3. Calyx, ovaries, and styles. — 4. Anthers, back and front view. — 5. Side view of an ovary cut vertically, and front view of a carpel full grown, showing the number and pendulous direction of the seeds. — 6. A seed with its arillus. All more or less magnified.
4th. — DlLLENIACEAE.
1. Flowering branch of Schumacheria castaneifolia natural size. — 2. Flower opened and seen from above, showing calyx, corolla, stamens, and ovaries, all in situ. — 3. Stamens removed.— 4. Anthers, back and front view. — 5. Ovary opened, showing the solitary ovule. —6. Seed and arillus. — 7. Immature seed, cut vertically, all more or less magnified. The outline below represents a full grown leaf natural size.