134 THE FUNGI WHICH CAUSE PLANT DISEASE 



Peridium firm, of roundish or angu- 

 lar, pesudo-parenchymatous, 



mostly dark, thick-walled cells 5. Mollisiaces, p. 146. 

 Ascocarps leathery, homy or cartilagi- 

 nous ; ends of the paraphyses united 

 into an epithecium 

 Peridium wanting or poorly devel- 

 oped 6. Celidiaces. 



Peridium well developed, mostly 

 leathery or homy 

 Ascocarps free from the beginning, 

 dish or plate-shaped, never en- 

 closed by a membrane 7. Patellariacese. 



Ascocarps at first embedded in a 

 matrix, then erumpent, urceo- 

 late or cup)-shaped, at first en- 

 closed in a membrane which 



disappears later 8. Cenangiaces, p. 150. 



Ascocarps borne on a highly developed 

 stringy or globoid stroma 

 Ascocarps at the ends of the branches 



of a cord-like stroma 9. Cordieritidaceae. 



Ascocarps embedded in the upper por- 

 tion of a globoid stroma 10. Cyttariacese. 



Lichenoid thallus more or less prominent, 

 algal cells typically present, asci disap- 

 pearing early, disk with a mazsedium. . 11. Caliciaces, p. 153. 



The Pyronemaceae, Peziacese, and Ascobolacese are pure sapro- 

 phytes on organic matter in the ground or on rotting wood. The 

 Patellariacese are largely, and the Celidiaceae are nearly all, para- 

 sitic on lichens. The Cordieritidaceae of four species, possessing 

 a stony stroma, are unimportant. The Cyttariacese, of one genus, 

 and some six species, are limited to the southern hemisphere where 

 they grow on branclies of the beech. 



Helotiacese (p. 133) 



In members of this family there is a distinctly differentiated 

 peridium. The apothecia are usually fleshy or waxy, superficial, 

 first closed, later opening; the paraphyses form no epithecium. 

 Asci 8-spored. Spores round to thread-shaped, one to 8-celled, 



