This two inch chiton has a wide girdle with sparse flat glassy hairs having several recurved spines at the base. The mucro is strongly posterior. The valves are beaked slightly. The central areas are longitudinally ribbed and where each rib touches the lateral area there is a granular pustule. These pustules form a heavy lateral rib. From this rib the centeral area rib continues at an oblique angle on the lateral areas until it again reaches a granular pustule at the posterior edge of the valve. These pustules form another granular rib along the posterior edge of each valve. This species exhibits the most variation in color of any West Coast species, ranging from dull gray, grays with white, greens with yellows, whites with yellows, greens with red, greens with maroon with white mixed in. It is altogether one of the most handsome species on this coast.
Illustrated specimens of color variations from Burghardt Collection