Cyathus is from a Greek word meaning a cup.
The peridium is composed of three membranes very closely related, closed at first by a white membrane, but finally bursting at the top. Sporangia plane, umbilicate, attached to the wall by an elastic cord.
Cyathus striatus. Hoffm.
Striate Cyathus.
Photo by C. G. Lloyd.
Figure 441.—Cyathus striatus.
The plants are small, obconic, truncate, broadly open; externally ferruginous, with a hairy tomentum, internally lead-color, smooth, striated.
The sporangia are somewhat trigonous, whitish, broadly umbilicate; covering of the cup thin, evanescent, somewhat thicker underneath, and cottony, often covered with down-like meal.