[Wikipedia] Description, Rarity: Streptanthus batrachopus is a rare species of flowering plant in the mustard family known by the common name Mt. Tamalpais jewelflower.[1] It is endemic to Marin County, California, where it is known only from Mt. Tamalpais and surrounding terrain. There are fewer than ten known occurrences.[2] Its habitat includes chaparral and coniferous forest, generally on serpentine soils. Description It is an annual herb producing a branching or unbranched stem up to about 20 centimeters in maximum height or slightly taller. Leaves near the base of the stem are oval or lance-shaped with toothed edges, somewhat fleshy in texture with a mottled pattern, and no more than 2 to 3 centimeters long. Leaves farther up the stem are lance-shaped. Flowers occur at intervals along the upper stem. Each has an urn-shaped calyx of purple or greenish sepals up to half a centimeter long. Purple or purple-streaked white petals emerge from the tip. The fruit is a straight or curving silique up to 3 centimeters in length. (link added by Mary Ann Machi)