Size and shape differences between museum specimens of the Orange-fronted Parakeet (Cyanoramphus malherbi) and the Yellow-crowned Parakeet (C. auriceps) are investigated using discriminant function analysis. No significant differences were found between the two groups, and the plotted discriminant scores show very poor separation, whereas the technique distinguishes both groups from Red-crowned Parakeets. These results support the view that C. malherbi is a colour variant of C. auriceps.