1 Polygalaceae R. van der Meijden Leiden) Herbs (sometimes saprophytic), shrubs, lianas or trees. Stipules absent but stem sometimes provided with a pair of glands at the nodes. Leaves simple, entire, usually spirally arranged, sometimes alternate, (semi)decussate or verticillate, sometimes scale-like or absent. Inflorescence usually raceme-like and un- and/or sometimes or fas- branched, (supra- or extra-)axillary terminal, thyrsoid ciculate, rarely flowers solitary. Bracts present; bracteoles basal, rarely (Salo- less monia, Epirixanthes) absent. Flowers bisexual, more or zygomorphous, rarely actinomorphous. Sepals 5, free and quincuncial, or the lower (abaxial) 2 connate, sometimes all connate, subequal or the lateral ones larger and then often wing-like (alae) and petaloid. Petals 3 or 5, free or variously united, occa- sionally also with the calyx, usually adnate to the base of the staminal tube or often with the lower often keel- the filaments, subequal or more unequal petal fila- like and frequently pouched, lobed, or crested. Stamens 2—10, usually 8, often ad- ments usually more or less connate except between the upper stamens, 1- nate to the petals; anthers basifixed, tetra- or bi-, rarely trisporangiate, or 2-locular, opening by a single and often oblique pore or by a longitudinal in- trorse slit. Ovary superior, usually 2-locular but occasionally 1-, 3-, 5-, 7- or but often dilated 8-locular, sessile or sometimes stipitate; style simple variously articulate with the and deciduous or lobed at apex, usually ovary nearly always fruits. Ovules cell and 4—more in a in 1 per subapical, or (in Xanthophyllum ) and 1-locular, bicarpellate ovary with 2 parietal placentas, anatropous, bitegmic crassinucellate. Fruit various, a berry, capsule, samara or drupe. 1000 Distribution. About 15 genera and over species, widespread in temperate and tropical America and South Africa. In Malesia regions of the world, especially well-developed in South 6 in genera, of which Polygala and Securidaca (not Australia) are cosmopolitan, Xanthophyllum The Eriandrawhich and Salomonia Indo-Australian, Epirixanthes Indo-Malayan. sixth genus is in belongs to the tropical American tribe Moutabeae, of which 3 genera are known South marked America; Eriandra occurs in New Guinea and the Solomon Islands and represents a ex- affinities. ample of disjunct, tropical trans-Pacific cold in the Ecology. Very diverse, in wet or dry, open or closed, warm or rather habitats, in habit. is a of small lowlands or on mountains up to 3600 m; greatly varying Epirixanthes genus litter the saprophytic (not parasitic) plants on humous soil in deep shade among of rain-forest. In are shrubs in the under- Salomoniais anunseemly herb of open places. Polygala there woody growth of the rain-forest, but most species are herbs of open country, several even preferring a of the like Securidaca. The seasonal climate; one species (§ Melchiora) is a climber rain-forest, species of Xanthophyllum and the monotypic Eriandraare trees of the rain-forest, sometimes of lofty size. has been dem- In some species of Polygala the occurrence of endomycorrhiza (VA-mycorrhiza) onstrated (HEUBL, 1984). but thusfar actual observa- Pollination. Most species seem to be adapted to cross-pollination, tions have only been reported for some Polygala species (see there). In Epirixanthes the structure there). Self-pollination, however, has been re- of the flowers seems fit for cross-pollination (see Professor Steenis: (1) For this revision the 1970 manuscripts have been used of three former students of Van and Mrs. H.M.Y.J. Andre de la F.C. Roest (Polygala sect. Chamaebuxus), L.P. Rijfkogel (Securidaca), Porte-Janss (Salomonia, Epirixanthes). 455 3 456 Flora Malesiana [ser. I, vol. 10 ported for species in diverse genera, also for those species in which cross-pollination has been is to be be concluded that is reported, or suspected possible. It may tentatively self-pollination an effective second-chance possibility for reproduction in the Polygalaceae. Dispersal. Corresponding to the diversity in fruit and seed types there is a great variationin dis- in persal types (VERKERKE, 1985). Especially Polygala many dispersal types occur: myrmeco- chory, ornithochory, anemochory, diplochory, epizoochory. Ornithochory also occurs in Dicli- danthera, Carpolobia, Atroxima, and probably in some Xanthophyllum species. Moutabeafruits have endozoochorous dispersal by monkeys (VAN ROOSMALEN, 1985); this may also be true for some Xanthophyllum species. Myrmecochory (or perhaps also anemochory) probably occurs in Bredemeyera, Comesperma, and Epirixanthes; anemochory also in Monnina and Securidaca (VAN ROOSMALEN, I.e.), but in the latter also hydrochory is possible. Epizoochory is the possible means of dispersal for Salomonia. References : HEUBL, Mitt. Bot. Staatssamml. Mtinchen 20 (1984) 222; VAN ROOSMALEN, Fr. Guianan Fl. (1985) 360; VERKERKE, J. Arn. Arb. 66 (1985) 385. Morphology. Recently the morphology and ontogeny of ovules, fruits and seeds have been described (and reviewed) by VERKERKE; of Polygala: VERKERKE & BAUMAN (1980); of Xantho- VERKERKE ofthe VERKERKE LEINFELLNER dem- phyllum: (1984); remaining genera: (1985). (1972) onstrated that there is no principal difference in the ontogeny of the unilocular, multiovulate the ovary of Xanthophyllumand the bi- to octoloculate, uniovulateovary of otherPolygalaceae. The ontogeny ofbi- and trisporangiate anthers ofPolygala has been described by CHODAT (1891) and VENKATESH (1956). Stipular outgrowths or nodal glands are pseudostipules in the sense of WEBERLING (VAN DER MEIJDEN, 1982: 3). Contrary to the idealisticopinion of CHODAT (I.e.) (also adopted by HUTCHINSON, 1967) and CRONQUIST (1981), the primitive numberof stamens is 8; the presence of 10 stamens (Diclidanthera; and a rare abnormality in Xanthophyllum) is a derived character. References : CHODAT, Monogr. I (1891); CRONQUIST, Integr. Syst. (1981) 763; HUTCHINSON, Gen. Fl. PI. 2 (1967) 338; LEINFELLNER, Oest. Bot. Z. 120 (1972) 51; VAN DER MEIJDEN, Leiden Bot. Ser. 7 (1982) 3; VENTAKESH, Bull. Torrey Bot. Club 83 (1956) 19-26; VERKERKE, Blumea 29 (1984) 409-421; J. Arn. Arb. 66 (1985) 353-394; VERKERKE & BOUMAN, Bot. Gaz. 141 (1980) 277-282. Vegetative anatomy. The Polygalaceae exhibit an interesting diversity in their leaf and wood anatomy, which has only fragmentarily been explored, especially for the Malesian genera. Hairs if present are unicellular, or more rarely uniseriate. The lower epidermis is papillate in a number of species. Stomatamay be ofthe anomocytic, paracytic oranisocytic type (all three types within the An in occur genus Xanthophyllum). adaxial hypodermis is frequently present the woody species with coriaceous leaves. The vascular pattern in petiole and midrib ranges from a single collateral bundle to a closed cylinder with accessory bundles (again the whole range of the is family represented in Xanthophyllum). The nodes are unilacunar. Unusual tracheoidal idio- blasts in the leaf mesophyll are characteristic for Xanthophyllum. The secondary xylem ofthe trees and climbers is characterised by largely solitary vessels with fibres with which simple perforations, distinctly bordered pits and heterocellular rays are usually narrow (1-2-seriate), but may be much wider in the Moutabeae (e.g. Securidaca). Axial paren- chyma is mainly paratracheal in Polygala, apotracheally diffuse and diffuse-in-aggregates plus vasicentric to loosely aliform in Securidaca, and apotracheally banded plus vasicentric in Xan- thophyllum. Included phloem occurs in the wood of Securidaca (and other Moutabeae). Despite the anatomical distinctness of Xanthophyllum (mainly through its tracheoidal idioblasts), vegetative anatomy clearly witnesses affinity with other Polygalaceae (epidermal characters, overall leaf histology, solitary vessels and fibre type in the wood; the parenchyma distribution in some Xanthophyllum species is reminiscent of that of Securidaca). In its wood anatomy Xanthophyllum also recalls Trigoniaceae, especially Trigoniastrum. References : BRIDGWATER & BAAS, IAWA Bull. n.s. 3 (1982) 1 15-125; DICKISON, Bot. J. Linn. 1988] Polygalaceae (van der Meijden) 457 Soc. 67 (1973) 103-115; METCALFE & CHALK, Anatomy of the Dicotyledons 1 (1950) 133-138; STYER, J. Arn. Arb. 58 (1977) 109-145. in Palynology. Pollen grains Polygalaceaeare mostly suboblate to prolate, sometimes equa- torially constricted ( Epirixanthes cylindrica), and measure from 25 to 62 pm. The apertural sys- is tem zonocolporate ('stephanocolporate') in all genera, the number of apertures ranging from 42 The 5 (Xanthophyllum papuanum) to 17, or up to in Polygala. endoapertures may be fused ('synorate') to form one broad, equatorial endoaperture, bordered by endexinous costae. In this way, the circle-shaped endoaperture divides a grain into two rigid halves, in which the colpi are no longeractive in harmomegathic functioning. Volume accommodation in such a grain, and pos- sibly also in grains with poorly separated pores, is achieved by folding of the flexible parts of the mesocolpia which cross the endoapertural zone (MULLER, 1979). Similar apertural systems and harmomegathic mechanisms occur in the genus Utricularia of the unrelated family Len- tibulariaceae (THANIKAIMONI, 1966; HUYNH, 1968). Exine stratification is mostly obscure using light microscopy. LARSON & SKVARLA (1961) dem- onstrated the presence of ectexine, endexine, and a columellateinfratectal layer inPolygala with electron microscopy. The tectum is mostly smooth, pitted, or perforate,