94 
Mycologia 
slightly ellipsoid. In addition to their form the spores when 
mature are covered with crevices which are so deep as to give to 
the outside of the spore a peculiar ragged appearance. As they 
mature, the spores become so dark that they are almost opaque. 
This species is also regarded as distinct and described below as 
Ascobolus subglobosus. 
In June, 1914, still another earth form had been collected which 
differed from any listed above in the fact that the apothecia were 
entirely white except the hymenium, which became darkened by 
the maturing spores. The spores and asci of this species were 
identical, so far as the writer could determine, with those of Asco- 
bolus carbonariiis but both color and habitat seemed to distinguish 
it from that species. Ascobolus carbonarius is restricted to burned 
places while this species grew on soil where there was no trace of 
fire. It may be that these plants represent only an albino form of 
Ascobolus carbonarius and that the white color is due to the fact 
that the plants have grown on an unfavorable substratum. The 
form is here listed as Ascobolus albinus. The following is a syn- 
opsis of the earth-growing species of Ascobolus as at present 
known for North America. 
Ascobolus Pers. in L. Syst. Nat. 1461. 1791. 
Apothecia sessile, or stipitate, superficial or partially immersed 
in the substratum, externally smooth or pilose ; hymenium con- 
cave, plane or convex; substance soft, fleshy or waxy, usually 
greenish ; asci cylindric to clavate or subovoid, 4-8-spored ; spores 
becoming blue or purple, fading to brown or blackish, ellipsoid to 
subglobose; smooth or rough; spore-roughenings very variable 
often consisting of crevices or cracks which give to the surface 
of the spore a reticulate appearance ; paraphyses slender and usu- 
ally adhering together in fascicles or clumps. 
Type species, Peziza stercoraria Bull. 
Plants restricted to burned areas. 1 . A. carbonarius. 
Plants not restricted to burned areas. 
Apothecia white, spores verrucose. 2 . A. albinus. 
Apothecia greenish to blackish, spores reticulate. 
Spores ellipsoid. 3- geophilus. 
Spores subglobose. 4- subglobosus. 
