Peziza repanda

Scientific name:  Peziza repanda Wahlenberg.
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.
Repand- means "folded backward, turned up" in
reference to the bent backward or turned down
margin observed in some specimens.
Synonyms: Aleuria repanda (Pers.) Gillet 
Common name(s):  Recurved cup
Phylum:   Ascomycota
Order:   Pezizales
Family:   Pezizaceae
Occurrence on wood substrate:  Saprobic; single
or clustered on decaying hardwood and adjacent
soil; spring through fall.  
Dimensions:  Cup to saucer-shaped, 6-12 cm
wide; stalkless but attached to wood by central
knob of tissue.  
Sterile outer surface:  Whitish, pale whitish-
brown; minutely pubescent.        
Fertile inner surface: Pale brown to dark brown;
smooth.
Edibility: Not recomended
Comments: The margin is sometimes folded in
toward the center of the cup. The MushroomExpert
site below lists 7 characteristic features of this species
that, together, clearly distinguish it from other brown
cup fungi. Unfortunately, one feature is the
microscopic examination of the spores.

More information at MushroomExpert.com: 
  

Figure 1. Note the white sterile surface, brownish fertile
surface, and recurved margin on this specimen.
Photo © Steve Nelsen.
    

Figure 2. Specimens collected during the 2013 NEMF
foray in Rimouski, Canada. Photo © Gary Emberger.


Figure 3. A cluster of recurved cups. Photo © Steve Nelsen.