Family: Campanulaceae (BELLFLOWER).
Other common names: few-flowered heterocodon, western pearlflower.
Generic common name: HETEROCODON.
Castro Crest: Backbone Trail, riparian woodland, May 2009.
Characteristics: Native, Blue, Small, Solitary, Simple, Herbaceous, Annual, Early Spring, Late Spring.
I have yet to catch its tiny blue flowers (a "rare" event.) Often cleistogamous (i.e., flowers do not open).