The stalked crinoids attach to the sea bottom using attachment structures
located at the end of the stalks or stems. The stem leads up to what is
known as the calyx, which is the base of the pentameral system of feeding
arms. The feeding arms have ciliated grooves, called ambulacral canals, that
capture suspended food
particles and direct the food back towards the mouth.
The primary diagnostic features of echinoderms are ambulacral
canals, the water vascular system, and pentameral symetry, all of which
are found in the majority of Crinozoa.