Stalked Crinoids

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.