482 COMPARATIVE MORPHOLOGY OF FUNGI 



spherical gleba. The collenchyma layer continues its growth, so that a 

 strong tension exists between it and the fibrous layer. This is increased 

 by the hydrolysis of the glycogen in the collenchyma layer to 

 maltose and by a consequent increase of osmotic pressure. Thereupon 

 the fibrous layer F separates from the pseudoparenchymatous layer P 

 and turns inside out, with the attached collenchyma, quickly and 

 forcibly (at times with a small report) ejecting the gleba S over 4 m. 

 high (the size of the fructification is a few millimeters!). Occasionally 

 the process is so forcible that the reversed part is thrown off. The 

 gleba that has been shot off germinates as a whole by putting forth 

 numerous germ tubes which largely develop from the gemmae, not 

 from the basidiospores. The gemmae are capable of germination for at 

 least seven years. 



In S. iowensis, development is similar to S. stellatus (Walker, 1927). 

 The secondary basidia by mutual pressure produce a chambered gleba 

 with well organized hymenia. The chambers early become filled with 

 spores. The palisade layer and the pseudoparenchyma next the gleba 

 is interrupted by strands of conducting tissue which connect the inner 

 and outer portions of the fructification. This species lacks the gela- 

 tinous layer in the peridium. 



Nidulariaceae. — The members of this family are characterized by 

 gleba chambers formed only in small numbers, surrounded by a special 

 sclerenchymatous wall and hence disseminated as a unit. The tendency 

 for the trama to split (which we found in Rhizopogon luteolus and in Pisoli- 

 thus) culminates in this family. 



In the forms so far studied, Crucibulum vulgare (Sachs, 1855), Cyathus 

 olla (C . fasicularis) (Walker, 1920) and Nidularia pisiformis (Fries, 1910), 

 the fructifications arise epigaeously on rotten wood as small knobs of 

 tissue (Cyathus olla may also be cultivated on artificial media). At the 

 periphery, the hyphae intertwine to a solid brown layer covered with hair- 

 like hyphae. This layer, the outer peridium ap, subsequently assumes 

 a corky consistency. On its interior, the light inner peridium ip is 

 differentiated by a predominantly peripheral arrangement of the hyphae 

 and a gelatinization of the hyphal walls. 



Shortly after the appearance of the inner peridium, the gleba chambers 

 are laid down in the ground tissue, and in Crucibulum (Fig. 307) and 

 Cyathus from the bases of the fructification toward the top, in Nidularia 

 in the apical part of the fructification only, while the basal part 

 becomes lacunose and its hyphae gelify. The formation of glebal 

 chambers proceeds in such a way that at any spot in the ground tissue 

 the young basidia, gradually increasing in number, grow toward the 

 common center where their ends come in contact. By the growth of the 

 basidial layer and by the enlargement of their surfaces, the basidial 

 tips are pushed apart so that in the chamber fundament is formed a 



