StreamPlot[{Cos[x + y^3], Sin[y + x^3]}, {x, -3, 3}, {y, -3, 3},
StreamPoints -> {pts -> Thick, Automatic, {Forward, Scaled[0.25]}},
Epilog -> {PointSize[0.015], Black, Point[pts]}, StreamScale -> None,
StreamColorFunction -> "Rainbow", ImageSize -> Large]