162 CYCLOBRANCHIATA.—CHITONIDZ. 
lated, and the margin of the mantle studded with 
little bundles of bristles, about nine or ten on each 
side. It varies in colour, but is generally greyish, 
or dusky olive. I have dredged it of large size 
in Weymouth Bay, attached to oyster-shells. A 
much smaller species is also common in that locality 
(C. cinereus), which occurs in the pools and on the 
ledges of the shore, near low-water mark. 
When put into a glass of sea-water, the Chitons 
are sluggish, often remaining for days rolled up 
before they begin to adhere, and then remaining 
a long time inert on the same spot. 
