"These small perennials from North America, closely related to Tiarella, are for shady places. They spread by runners and soon cover the ground." (Kohlein).
Mitella breweri:
Native to British Columbia, evergreen, with small rounded
deep-green leaves. The flower stems are 25 cm hight, and the
flowers small and greenish.
Mitella caulescens:
Leaves are heart-shaped and with regular serrations. The
entire plant is covered with coarse hairs. Flower stems are
10-15 cm and carry inconspicuous yellow flowers.
Mitella diphylla: From
Eastern North America, this is the most widely distributed species.
Mitella nuda: A little
known species from North America. The leaves are rounded
and kidney-shaped, flowers greenish.
Mitella pentandra:
The basal leaves are kidney-shaped. Flower stems 25-30 cm high,
bearing small yellowish flowers with plumed petals.
Mitella trifida: Leaves
heart-shaped; Flower stems 10-15 cm high, carrying a dense
one-sided cluster of small white flowers.
(Kohlein, F. 1984)