The underside of this species is composed of a flat foot with a row of gills along each side (gills not visible in this photo). The edges of the mantle form a wide belt around the foot. Photographed by Dave Cowles at San Simeon, CA 1995
Another photo of the underside. Photo by Dave Cowles, San Simeon, CA April 1997 This species was formerly abundant at San Simeon, CA. During the latter years of the 1990's I (Dave Cowles) observed large numbers decomposing and washing up onto the beach. I suspect a disease was affecting them. Those washing ashore were blotched, as some living individuals are. I wonder if the blotching seen in living individuals is a sign of disease? Far fewer can be found there now.
