Round-leaf Vitex, Beach Vitex
This Vitex can be found on the Hawaian beaches at the tide line, forming extensive colonies. It has silvery aromatic leaves. Its flowers are short bluish purple spikes, about half an inch long, in summer, followed by 1/4 inch in diameter (6 mm) bluish-black fruits.
The species name "rotundifolia" comes from the Latine for "round-leaved".