Palm trees of the Amazon and their uses

The stem of this species is about an inch in diameter and ten or twelve feet high, thickly set with flat black spines disposed in rings. The leaves are rather large and irregularly pinnate, the leaflets being in little groups of two or four, standing out at various angles from the midrib, the groups themselves being set alternately along it. The leaflets are elongate and have the midrib produced in a bristly point, and the terminal pair are not larger than the rest. The petioles are armed with flat whitish spines, which on the long sheathing bases become black.

I met with this palm only once, growing in the dry virgin forest on the banks of the Rio Negro. Though it had neither flowers nor fruit at the time, yet its habit is so peculiar as to leave little doubt of its being a new species. It seems most nearly allied to the Bactris macroacantha of Martius.