I'm not sure if this is one of those post that have been answered so mony times that people dont want to be bothered answering again, but I was curious as to the answer. I did a little research and found this info for you:
Common Name: Feather Duster Worm
Classification: Kingdom Animalia, Phylum Annelida, Class Polychaeta
Identification: leathery tube about 20 centimeters long, cirri at mouth with cilia, cirri look like branched feathers
Typical Habitat: marine, intertidal
Abundance: found on floats near shoreline on Pacific NW shores
Energy/feeding: particle feeders
Reproduction: sexual, release eggs and sperm into water
Trivia: move feces out of the tube-like "shell" by "conveyor belting" it up and out the top near the head
References: Kozloff, E.N. 1983,1993. Seashore Life on the Northern Pacific Coast
I didnt see ANYWHERE that they multiply by splitting, but that doesnt mean that it cant happen, it's all I could find. Hope it helps you out!
Mike