Where Primroses (Primula vulgaris) and Cowslips (Primula veris) grow in close proximity they will occasionally hybridise to produce the False Oxlip (Primula vulgaris x veris = P. x polyantha). Though this is not really clear from my images, the hybrid is usually a larger plant than the Cowslip, and I think it combines the prettiest traits of both parents to produce a real stunner!