Evolutionary tracks in the Δlog (N/H) vs. plane, with Δ(N/H) = log ⁽N/H⁾_t − log ⁽N/H⁾_ini, where (N/H)_t is the ratio of the nitrogen to hydrogen abundance (in number) at the surface of the star at the time t. The tracks are from models with M_ini = 3, 4, 5, 7, and 9   M_⊙ (from right to left). The solid red lines are for the models at Z = 0.002 and the solid blue lines correspond to the models at Z = 0.014 from Paper I. The dotted red line correspond to the non-rotating 7   M_⊙ model at Z = 0.002.