Manual of the Trees of North America (Exclusive of Mexico) 2nd ed.

Stem simple; leaves stalked.

Leaves fan-shaped.

Leaf stalks unarmed.

Rachis short; leaves usually silvery white below.

Leaves 2°-4° in diameter (green below in No. 2), their segments undivided at apex.

Thrinax (p. 96).

Leaves 18′-24′ in diameter, their segments divided at apex.

Coccothrinax (p. 100).

Rachis elongated; leaves green below, their segments divided at apex.

Sabal (p. 101).

Leaf stalks armed with marginal teeth or spines.

Leaf stalks furnished irregularly with broad thin large and small, straight or hooked spines confluent into a thin bright orange-colored cartilaginous margin; leaves longer than wide, divided nearly to the middle into segments parted at apex and separating on the margins into thin fibres.

Washingtonia (p. 104).

Leaf stalks furnished with stout or slender flattened teeth; leaves suborbicular, divided to the middle or nearly to the base into segments parted at apex; segments of the blade not separating on the margin into thin fibres.

Ac?lorraphe (p. 105).

Leaves pinnate.

Leaves 10°-12° in length, their pinn? 2?°-3° long and often 1?° wide, deep green.

Roystonea (p. 107).

Leaves 5°-6° long, their pinn? 18′ long and 1′ wide, dark yellow-green above, pale and glaucous below.

Pseudoph?nix (p. 109).

Stem simple or branched; leaves sessile, lanceolate, long- and usually sharp-pointed at apex.

Yucca (p. 110).