Given a smooth, closed, oriented 4–manifold X and α in
H2(X,Z) such that α·α>0,
a closed 2–form ø is constructed, Poincaré dual
to α, which is symplectic on the complement of a finite set of
unknotted circles Z. The number of circles, counted with sign, is given
by d=(c1(s)2-3σ(X)-2χ(X))/4, where s is a
certain spinC structure naturally associated to ω.