Mt. Tamalpais jewelflower
On a bare serpentine outcrop high above the Pacific ocean is a low leafless stalk with a few small purple flowers. This is the Mt. Tamalpais jewelflower, a sub-species of Streptanthus glandulosus which is found only in Marin County. Though the plant is unassuming, when you look close the flowers have earned their name. Narrow, crinkled petals flare out above a colorful pouch that is faceted and luminous like a gem.
The jewelflower is in the same family as radish and milkmaid. The long, narrow, fleshy seed pods that are pictured below are typical of the family, though the unusual flowers are not! I saw this beauty, S. glandulosus ssp. pulchellus, near Rock Springs on Mt. Tam during the MMWD/Cal Academy Bioblitz last weekend, and owe thanks for the ID to Terry Gosliner. I wrote about secund jewelflower back in May – which is also a sub-species of S. glandulosus, and the only jewelflower in Marin that isn’t listed as either rare or endangered. 
Flowers Of Marin 