Abstract. Let C be a family of curves over a non-singular variety S. We study algebraic cycles on the relative symmetric powers C [n] and on the relative Jacobian J. We consider the Chow homology CH * (C [•] /S) := ⊕n CH * (C [n] /S) as a ring using the Pontryagin product. We prove that CH * (C [•] /S) is isomorphic to CH * (J/S)[t] u , the PD-polynomial algebra (variable: u) over the usual polynomial ring (variable: t) over CH * (J/S). We give two such isomorphisms that over a general base are different. Further we give precise results on how CH * (J/S) sits embedded in CH * (C [•] /S) and we give an explicit geometric description of how the operators ∂ [m] t and ∂u act. This builds upon the study of certain geometrically defined operators Pi,j (a) that was undertaken by one of us in Part 1 of this work, [18].Our results give rise to a new grading on CH * (J/S). The associated descending filtration is stable under all operators [N ] * and [N ] * acts on gr m Fil as multiplication by N m . Hence, after − ⊗ Q this filtration coincides with the one coming from Beauville's decomposition. The grading we obtain is in general different from Beauville's.Finally we give a version of our main result for tautological classes, and we show how our methods give a simple geometric proof of some relations obtained by Herbaut and van der Geer-Kouvidakis, as later refined by one of us in [14].