The calyptra (fig. 24) is half-cleft (dimidiate) and very hairy.
Dimidiate, halved; as where a leaf or leaflet has only one side developed.
The stem is wanting, and the cap is shelving, dimidiate, reniform or suborbicular.
Dimidiate, halved, said of a sessile pileus semi-circular in form and attached by the plane edge directly to the wood.
Dimidiate -us: halved; extending ...