Calyx   

A calyx is a set of teardrop-like sepals (leaves) on a cannabis plant that are part of the female flower. Calyxes usually contain a high concentration of trichomes, and they appear in various colours, shapes and sizes.

In fertilised plants, the calyxes act as the breeding ground for the plant's seeds. Keeping the calyxes seedless will result in larger and more potent buds.