Polychaete Worm: Glycera macrobranchia. Each body segment has a pair of parapodia - literally "side feet". "Glycerids are the "bloodworms", a popular bait used by salt water fishermen. They're benthic carnivores, crawling on or just under the sediment to hunt for prey, typically other worms, small molluscs & crustaceans, etc. Swimming is usually associated with spawning so possibly that's why your critter was up & out."
6 miles offshore, Palos Verdes, California
ID thanks to Leslie Harris
![Polychaete Phyllodoce cf groenlandica or Phyllodoce medipapillata<br />
ID thanks to Leslie Harris - "These are the two biggest species of Phyllodoce on this [SoCal] coast. Most polychaetes do have legs which are collectively called parapodia (or parapodium for just one). The setae (= bristles) emerge from the parapodia which sometimes have upper & lower flaps of skin called the dorsal and ventral cirri. What you called legs Kev, are enlarged dorsal cirri. These help the worm move and give the family it's common name - the paddle worms."<br />
Catalina Island, California USA](https://photos.smugmug.com/NorthAmerica/Invertebrates-Eastern-Pacific/Invertebrates-Annedlida/i-N2BPChG/1/4c2d302f/Ti/Worm_090626b_w-Ti.jpg)
