How do echinoderms catch their prey?

There are a variety of ways that echinoderms catch their prey, depending on the species.  Crinoids and some of the brittle stars are filter feeders and eat plankton and small fish.  Crinoids tend to extend a net in which they catch unsuspecting prey.  Sea urchins tend to graze for their food along the ocean floor.  Sea cucumbers are deposit feeders, feeding on what the tides leave behind when they go out.  The starfish are active hunters that use their tubed feet to catch prey and hold it in place while they feed.  However, some species of starfish mimic the feeding techniques of the crinoid, while others get their food by extracting it from the mud.  When starfish find their prey and pry open the shell, they inject gastric juices into the creature and suck it out.