Distribution. Often forming extensive groves or small isolated clumps in wet usually alkali soil in depressions along the northern and northwestern margins of the Colorado Desert in southern California, sometimes extending for several miles up the cañons of the San Bernardino and San Jacinto mountains; and in Lower California.

Now largely cultivated in southern California, New Orleans, southern Europe, and other temperate regions.

5. ACŒLORRAPHE H. Wendl.

Trees, with tall slender often clustered stems clothed for many years with the sheathing bases of the petioles of fallen leaves. Leaves suborbicular, divided into numerous two-parted segments plicately folded at the base; rachis short, acute; ligule thin, concave, furnished with a broad membranaceous dark red-brown deciduous border; petioles slender, flat or slightly concave on the upper side, rounded and ridged on the lower side, with a broad high rounded ridge, thickened and cartilaginous on the margins, more or less furnished with stout or slender flattened teeth; vagina thin and firm, bright mahogany red, lustrous, closely infolding the stem, its fibres thin and tough. Spadix paniculate, interpetiolar, its rachis slender, compressed, ultimate branches, numerous, slender, elongated, gracefully drooping, hoary-tomentose, the primary branches flattened, the secondary terete in the axils of ovate acute chestnut-brown bracts; spathes flattened, thick and firm, deeply two-cleft and furnished at apex with a red-brown membranaceous border, inclosing the rachis of the panicle, each primary branch with its spathe and the node of the rachis below it inclosed in a separate spathe, the whole surrounded by the larger spathe of the node next below. Flowers perfect, minute, sessile on the ultimate branches of the spadix, in the axils of ovate acute chestnut-brown caducous bracts, solitary toward the end of the branches and in two- or three-flowered clusters near their base; calyx truncate at base, divided into three broadly ovate sepals dentate on the margins, valvate in æstivation, enlarged and persistent under the fruit; corolla three-parted nearly to the base, its divisions valvate in æstivation, oblong-ovate, thick, concave and thickened at apex, deciduous; stamens six, included; filaments nearly triangular, united below into a cup adnate to the short tube of the corolla; anthers short-oblong, attached on the back below the middle, introrse, two-celled, the cells opening longitudinally; ovary obovoid, of three carpels, each with two deep depressions on their outer face, united into a slender style; stigma minute, terminal, persistent on the fruit; ovule solitary, erect from the bottom of the cell, anatropous. Fruit drupaceous, subglobose, one-seeded, black and lustrous; exocarp thin and fleshy; endocarp thin, crustaceous; seed erect, free, subglobose, light chestnut-brown; testa thin and hard; hilum small, suborbicular; raphe ventral, oblong, elongated, black, slightly prominent, without ramifications; embryo lateral; albumen homogeneous.

Two species of Acœlorraphe have been distinguished; they inhabit southern Florida, and one species occurs also in Cuba and on the Bahama Islands.

The generic name, from ἀ priv., Κοῖλος and ῥαφη, refers to the character of the seed.

CONSPECTUS OF THE NORTH AMERICAN SPECIES.

Petioles furnished with stout marginal teeth throughout their entire length; leaves green on both surfaces, their primary divisions extending to the middle, secondary divisions only from 3½′—9′ long; stems forming large thickets.1. [A. Wrightii] (D). Petioles furnished with thinner teeth, usually unarmed toward the apex; leaves green or glaucescent on the lower surface, their primary divisions extending nearly to the base, secondary divisions often 10′ long or more; stems often prostrate.2. [A. arborescens] (D).

1. [Acœlorraphe Wrightii] Becc.