1. Blades of mid- and upper (if not lower) cauline leaves divided below the middle into coarsely toothed to pinnatifid lobes.

2. Pedicels and outside of calyx with many short stellate hairs sometimes overtopped by longer simple hairs; bractlets subtending calyx at most 3 times as long as broad.

M. alcea

2. Pedicels and outside of calyx with only simple hairs (rarely a few stellate ones); bractlets subtending calyx usually 3-5 times as long as broad.

M. moschata

1. Blades of all leaves shallowly (if at all) divided or lobed (less than halfway to their base).

3. Petals ca. 15-24 mm long, deep pink to purple; bractlets subtending calyx oblong-ovate, less than 3 times as long as broad.

M. sylvestris

3. Petals less than 15 mm long, white (sometimes with pinkish veins, tips, or shading); bractlets subtending calyx more than 3 times as long as broad.

4. Leaf blades undulate or puckered along the margin; most flowers sessile or nearly so; stems erect.

M. verticillata

4. Leaf blades flat; most flowers at anthesis on pedicels longer than the calyx; stems ± prostrate or ascending.

5. Petals at least 1.5-2 times as long as the sepals; carpels 12-14 (-15), at maturity smooth (or very obscurely reticulate) and short-pubescent on the outer surface.

M. neglecta

5. Petals barely if at all exceeding the sepals; carpels 9-11, at maturity strongly reticulate and glabrate on the outer surface.

M. pusilla