Graceful and slender, growing in open but not crowded large colonies; trunk 3-6 m. tall, about 4 cm. thick, irregularly ringed with brown-black bulbous- based spines 3-8 cm. long that are ascending on upper parts of bole and more or less declined on lower parts, the intermediate blank spaces often as much as 15 cm. long, the plant spreading by means of subterranean stems: leaf-blades 2 m. more or less long, glossy, thin in texture, interruptedly pinnate; petiole 1 m. or more long, slender, sometimes furfuraceous, nearly terete, bearing light-colored spines 1-3 cm. long toward the base and otherwise unarmed, rachis usual- ly unarmed; pinnae about 25 subopposite pairs spaced 5-8 cm. apart, to 75 cm. long and 4-5 cm. broad, glabrous, midrib prominent and side-veins sometimes nearly equally so, margins minutely setulose, apex prolonged into a narrow nearly or quite caudate part, this part particularly slender and conspicuous on the broad pinnae of young plants: cymba or spathe 20-30 cm. long, densely brownish or tawny-setose: fruit turbinate, 2-2.5 cm. long, black, with abrupt short stout beak, glabrous; cupule double with bluntly scalloped edges; nutlet about 12 mm. either way, flattened on top, contained within a fibrous mesocarp.