The Base (E.G
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Celastraceae—I Ding Hou Leyden) Trees, erect or scandent shrubs; stems sometimes producing rootlets (Euonymus spp.), rarely buttressed at the base (e.g. Bhesa) or with aerophores (Lophopetalum elastic resin- multinervium), sometimes thorny (Maytenus spp.); sometimes with or ous threads in the leaves, inflorescences, floral parts, fruits, or branchlets, show- ing on fractures. Leaves simple, alternate, spiral, decussate or opposite, some- times fascicled on short branchlets, penninerved, sometimes black-dotted be- neath, rarely so on both surfaces, often crenate, more rarely entire. Stipules small, simple or laciniate, caducous, or none. Inflorescences axillary and/or ter- minal, sometimes extra-axillary, or ramiferous, cymose, thyrsoid, paniculate, racemose, fasciculate, sometimes 1-flowered, usually bracteate. Flowers generally small, actinomorphic, bisexual or unisexual, in the latter case the plants usually dioecious or sometimes polygamous. Calyx 4- or 5-lobed, lobes imbricate, val- rarely valvate, usually persistent. Petals 4 or 5, imbricate, contorted, rarely vate, caducous, sometimes persistent, rarely slightly connate at the base and s ometimes also united with the staminal ring below the connate filament bases (i.e. the surface sometimes so-called ‘disk’ in Microtropis), upper usually smooth, Partly covered with cristate, lamellate, fimbriate, or fleshy papilla-like appendages (e .g. Lophopetalum). Stamens (2-) 3, 4, or 5, rarely 8-10 (extra-Mal. gen.Forsellesia), alternate with the petals (except in Forsellesia), filaments inserted on or within the disk, on its margin or slightly below it, or on a basal ring (Microtropis ), ca- ducous or persistent; anthers mostly 2-celled, very rarely 1-celled (extra-Mal. spp.), usually ovoid, ellipsoid, or subglobose, rarely reniform, sometimes diver- gent, longitudinally, laterally, or very rarely apically (extra-Mal. spp.) dehiscent, introrse or extrorse, basifixed, dorsifixed, or dorso-basifixed. Disk various, often Present and conspicuous, fleshy or membranous, patelliform or cupular, or flat, e ntire, dentate, angular, or lobed; extrastaminal to intrastaminal, sometimes a dnate to the torus or partially free at the margin, usually annularand continuous, rarely discontinuous and lobed, or even forming staminiferous pockets (extra- Mal. genera Cheiloclinium and Apodostigma), rarely obscure (Microtropis), dually smooth, rarely covered with papilla-like or fleshy subulate processes). Ovary partly or entirely immersed in the disk, sometimes concealed within it or a dnate to it, or free from it, usually glabrous, sometimes with a tuft of hairs at the top (Bhesa), rarely puberulous (extra-Mal. spp.), or covered with papilla- like or fleshy subulate processes at the base (Euonymus spp.), (l-)2-5-celled or ra rely many-celled (Siphonodon), mostly completely, very rarely incompletely in hollow the felled; usually ending a style, or very rarely at top (Siphonodon; style distinct, short, or obscure, or lacking (Brassiantha, Siphonodon and extra- Mal. genus), simple, rarely almost divided to the base (Bhesa), terminal, rarely lat eral in fruit (Pleurostylia); stigma(s) simple, or lobed. Ovules mostly 2 in each cell, sometimes 1, or 3-18, anatropous, inserted at the inner angle, erect and inserted at the base or slightly higher, or pendulous, collateral, superposed or in 2 series. Fruit capsular, loculicidal or with 3 divergent separate or laterally con- nate ‘follicles’, or drupaceous, dehiscent, and sometimes leaving a columella, or indehiscent, smooth, sometimes echinate. Seeds erect or pendulous, sometimes aril when winged; present or none, present usually partly or entirely enveloping 227 3 228 FLORA MALESIANA [ser. I, vol. 6 the seed or cushion-like situated the base of at it; usually orange or orange-red, rarely white; albumen present or 0; embryo erect; cotyledons flat, foliaceous. Distribution. The Celastraceae family (includingHippocrateaceae) comprises c. 90 genera and over 1000 distributed in spp., both hemispheres except the arctic regions, predominantly occurring in the tropics and subtropics. The in Ecology. Malaysian spp. occur mostly primary, occasionally in secondary rain-forests, some in peat or freshwater swamp forests. shrubs small trees of the They are mostly or substage, some species are climbers, but some may grow to large-sized trees, of Bhesa, Kokoona, Lophopetalum and e.g. spp. , at low and medium but 1000 up Siphonodon. They commonlyoccur altitudes, some species grow above m to 3200 m, e.g. species of Euonymus, Microtropis, and Perrottetia. Almost all to everwet Malaysian species are adapted climatic conditions but afew, notably Maytenus and Cassine glauca (ROTTB.) O.K. prefer sp. or are characteristic for seasonally dry climatic conditions and and are consequently found in Central East Java and the Lesser Sunda Islands. Cassine viburnifolia (Juss.) DING HOU is a typical mangrove plant. Some species occur in peat swamps, notablyLophopetalum multinervium RIDL., L. sessilifolium RIDL., L. rigidum RIDL., L. javanicum (ZOLL.) TURCZ. (occasionally), and Kokoona ovatolanceolata RIDL- Under such conditions L. multinervium RIDL. possesses prominent buttresses and cylindrical aero- phores (fig. 13). The only spiny plants occur in the genus 1Maytenus. Pollination. The flowers ofmost ofthe members ofthis family have nectariferous diskswhich sometimes marked contrast with the colour show a ofthe ovary or some other floral parts and are visited by various kinds of insects, e.g. ants, bees, beetles, and flies. Some species are dioecious, or polygamous and require presumably insect-pollination. Unfortunately we have no pertinent data on pollination of tropical Celastraceae. Dispersal. The seeds of most of the members of this family are generallyprovided with a bright-col- oured aril which contrasts to the colour of the covered pericarp and testa, if the latter is only partially by the aril. These arillate seeds are a great attraction to birds. In Celastrus the ripe fruits are with seeds enclosed in usually yellowish a showy red or golden-yel- lowish in the fruits the In aril; widely opening bright-coloured arillate seeds display a showy contrast. Glyptopetalum and some Euonymus spp. the arillate seeds are hanging out from the capsules. The cap- sules of and of seeds Microtropis some species Bhesa are splitting lengthwise on one side exposing the covered with bright-coloured arils lying inside. seeds of The winged Lophopetalum and Kokoona are wind-dispersed. fruits Some of the drupaceous fruits, e.g. in Cassine (syn. Elaeodendron), are also bird-dispersed. The of African Cassine have been to be the fo- some spp. reported dispersed by elephants, which browse on the fruit with the liage swallowing it; seed germinates well after having passed the digestive tract. tidal In Elaeodendron subrotundum = Cassine Malaysia viburnifolia (Juss.) DING HOU occurs along rivers and seashores. Its fruit has a thin and according exocarp a not evenly thickened, corky mesocarp; to RIDLEY it is well adapted for sea-dispersal (Disp. 1930, 120, 267, 357, 426). It is remarkable that in some species of fruits do mature Microtropis full-grown not contain a single seed. The fruits I of contain either be saw Pleurostylia no seed or this was damaged by insects. It could that this of seed is correlated with the deficiency setting very restricted distribution or rarety of species of these genera. Elastic threads. In fruits, Morphology. breaking young leaves, branchlets, inflorescences, floral parts, or seeds of species, the two threads, some parts remain sometimes connected by a number of fine, elastic in the leaves of the African acuminatus They e.g. Maytenus and spp. of the American genus Wimmeria. can be dissolved in benzene and are classified as gutta-percha. ot The funicle of the S. American is also of fine threads but these are - - - * Maytenus magnifolia- composed „ „ 01 an entirely different nature, namely spiral thickenings of vessels such as found under the seeds Talauma, Magnolia, and other Magnoliaceae. The loosening ofspiral thickenings from vessels is not un- in but to common Monocotyledons, according Dr. METCALFE it is probably more rare in Dicotyledons- e Floral tube and disk. In the celastraceous flower there is generally a conspicuous cupular or plate-lik structure which is commonly called the disk. AND BERKELEY (J. Elisha Mitchell Sc. Soc. 69, 1953, 185-206, t. 3-4) has studied the floral morphology ~ of of the anatomy some representatives Euonymus, Celastrus (2 spp.), and Pachistima. He interpreted in Celastrus C. scandens and C. but cup-shaped structure (i.e. orbiculatus), which surrounds the ovary be- is free from it, as a 'floral tube' consisting of the fused basal portions of the floral whorls. The tissue the he called the 'disk' and Th® tween stamens considered it to represent the vestiges ofreduced stamens. broad flat structure the in to flora' surrounding ovary, e.g. Euonymus, the edge of which are attached the whorls he also interpretedas being a 'floral tube' comparable to that ofCelastrus; the 'disk' is considered to the in Celastrus occupy same position as and has been given the same interpretation. The 1 Bo term disk used in this treatment, as have done in my revision of Celastrus (rf. Ann. Mo. • 11 Gard. 42, 1955, 220) is equivalentto the'floral tube' ofBERKELEY while what I call disk lobes is equivale to his 'disk'. Dec. 1962] CELASTRACEAE (Ding Hou) 229 Arils and -arillodes. to PLANCHON Ann. Nat. Sc. t. f. According (cf.. Ill, 3, 1845, 281, 308, 11, 3-5, „ w f. the