[1] The largest remaining population of this shrub occurs on Mt.

[2] The Ceanothus purpureus plant grows in woodland and chaparral habitat.

It is spreading or erect in form, approaching 2 meters in maximum height.

They are round to oval, wavy, and edged with spiny teeth, resembling the leaf of holly.

The fruit is a horned capsule about half a centimeter long.