five-toothed

The calyx is adnate in relation to the ovarium, limb very short, but free and five-toothed; the corolla is funnel-shaped, but split at the back, causing it to appear one-sided.

Hardy Perennials and Old Fashioned Flowers Describing the Most Desirable Plants, for Borders, Rockeries, and Shrubberies. John Wood

The flowers, which are about ½in. across, are of a pink colour, and produced on many-branched prostrate stems; the calyx is five-toothed; the corolla is formed of five flat petals; the leaves are small, basil-like, oval-lance shaped, entire and smooth; the general appearance of the plant when in bloom is that of a compact mass of small leaves and flowers, the latter predominating.

Hardy Perennials and Old Fashioned Flowers Describing the Most Desirable Plants, for Borders, Rockeries, and Shrubberies. John Wood