Flora of New Zealand Series

Rhizomatous or tuberous, scapose or caulescent, perennial herbs or vines, rarely shrubs, small trees or aquatic herbs; hermaphrodite, monoecious or dioecious; often with milky, watery or pungent sap and tissues rich with crystals of calcium oxalate. Leaves solitary or few, mostly basal; laminae often hastate or sagittate, parallel- or net-veined, sometimes large and fleshy; petioles sheathing. Inflorescence a thick fleshy cylindric spadix, often ± enclosed in a terminal spathe. Flowers minute, actinomorphic, ebracteate, densely crowded over whole, or lower part of spadix, female flowers at base of spadix, male flowers above, occasionally with sterile flowers interspersed, or in a band above both male or female flowers. Spadix with or without terminal sterile appendage. Perianth present in bisexual flowers, segments 4-6, usually lacking in unisexual flowers. Stamens 1-many, free or ± connate; anthers usually 2-celled, opening by pores or slits. Ovaries 1-many, superior, 1-3-(many)-locular with 1-many ovules in each locule; style usually very short, occasionally 0. Fruit a berry, 1-many-seeded. Over 100 genera, mainly of tropics and subtropics but some in temperate regions.

Fig. 13. ARACEAE: A: Arum italicum, Italian arum; spadix. B: Dracunculus vulgaris, stink lily; leaf showing B1 light markings, B2 mottled sheath. © All rights reserved. [Image: 26WY]

Fig. 14. ARACEAE, leaves; A: Alocasia macrorrhiza, elephant' s ear. B: Zantedeschia aethiopica, arum lily. C: Arum italicum, Italian arum. D: Colocasia esculenta, taro. © All rights reserved. [Image: 26WZ]