Annelids I: Polychaetes
Polychaeta - bristle worms; motile or sessile (fan worms)
Head well-developed with eyes, brain
Parapodia on all but first and last segments: paddle-like flaps with bristle-like setae
Gonads lacking; gametes produced from lining of coelom; mature worms degenerate intestine and muscles, segments filled with gametes
Trochophora larvae similar to those of mollusks