Sderotinia fructigena. 93 



College Park about April 1 ; the last ones I observed in perfect 

 condition there were seen on April 27. The duration of the 

 ascospore stage is then about that of the peach flowers. The 

 single apothecia last only two or three weeks, after that 

 drying up so as to be found with difficulty. 



The apothecia arise from the familiar sclerotia in the 

 tissues of the so-called mummy fruits beneath the soil or 

 occasionally on the surface in moist places. Usually several 

 arise from the under side of each fruit and appear in a ring 

 around it at the surface of the ground, from one to twenty 

 appearing above one fruit. 



The sinuous stipe is from .5-3 cm. long, depending on the 

 length it must grow to bring the spore-bearing surface above 

 the ground. It is from .3-1.5 mm. thick. The lower part is 

 covered with closely adherent particles of soil entangled in a 

 mass of slender dark-colored septate rhizoids 1 mm. or less 

 in length. These gradually disappear upward, the upper part 

 of the stipe being smooth. The color is dark brown below 

 running into the lighter brown of the disk above. The body 

 of the stipe is made up of somewhat elongated cells in the 

 center with shorter dark-colored cells on the outside, com- 

 posing the cortex which continues around the outside of the 

 disk and projects at the edges somewhat beyond the hymen- 

 ium. The subhymenium is composed of elongated inter- 

 twined cells much like those in the center of the stipe. 



The stipe enlarges into the at first campanulate disk, 

 slightly broader below the top. The disk widens out until 

 cup-shaped and finally flat. Older ones often have the edges 

 torn and recurved. The disk becomes again campanulate in 

 drying up and is then darker colored. The expanded disk is 

 from 2-15 mm. wide, usually about 5-8 mm. In its later 

 stages it is often whitish from a deposit of spores. 



The line of demarcation seen in sections between the 

 hymenium and subhymenium is composed of a dense mass of 

 small hyphae from w^hich the asci and paraphyses arise. 

 These are of the usual form of the Pezizaceae and of the 

 genus. The paraphyses are very slender and slightly en- 

 larged at the apex. The asci are 45-50 /* long and 3-4 /t« 

 wide, with 8 spores in the apical half. 



