RIBBON WORMS

Slender, quite delicate and highly contractile, ribbon worms have a digestive system with a separate mouth and anus, as well as a circulatory system complete with blood vessels. Most unique, though, is the proboscis or food capturing device, shown in the photograph of a chevron ribbon worm (NE5). Like a fluid-filled, inside-out finger of a glove, the proboscis is either sticky or has a venomous, thorn-like stylet on the inside. On a massive muscular contraction of the proboscis, hydrostatic pressure everts it to envelop prey—often a segmented worm.
At least 87 species of ribbon worms live in the marine waters of the Pacific Northwest.