Peziza badioconfusa

Scientific name:  Peziza badioconfusa Korf
Derivation of name: The derivation of Peziza is
somewhat uncertain. One source indicates it is an
ancient term for a mushroom with little or no stalk.
Badi- means "reddish-brown" and confusa implies
this fungus can be confused with Peziza badia.
Synonyms:  Peziza phyllogena Cooke
Common name(s):  Common brown cup
Phylum:   Ascomycota
Order:   Pezizales
Family:   Pezizaceae
Occurrence on wood substrate:  Saprobic; solitary
or clustered on the ground or well-decayed wood
(especially moss-covered stumps); spring through
early summer.  
Dimensions:  Up to 10 cm wide; deep to shallowly
cup-shaped, flattening with age; stalkless.   
Sterile outer surface:  Reddish-brown; dull,
scurfy.       
Fertile inner surface:   Reddish-brown; smooth.
Edibility: Edible
Comments: Although this fungus resembles Peziza
badia, P. badia fruits in the fall. The two species also
differ in spore morphology.  

More information at MushroomExpert.com:

Figure 1. Typical specimen of Peziza badioconfusa.
The cups become quite irregular in shape when
growing in clusters. Photo © William Roody