ORDER PEZIZALES: SUBORDER INOPERCULATAE 



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Fig. 79. Pezizales, Family Mollisiaceae. Diplocarpon earlianum (E. & E.) Wolf. 

 (A) Acervulus of Marssonina stage. (B) Section through apothecium. (Courtesy, 

 Wolf: /. Elisha Mitchell Sci. Soc, 39(3-4) :141-163.) 



upon dead leaves, sometimes under a superficial radially arranged shield- 

 like stroma, sometimes not. The parasitic stage produces the conidial 

 form known as Adinonema when the radiating dark hyphae are present, 

 or Marssonina in their absence, or Entomosporium when the conidia have 

 hair-like appendages. On various species of Prunus there occur several 

 species of fungi whose conidial stage forms the genus Cylindrosporium. 

 It is this stage which is parasitic and causes great damage to the leaves 

 of plums and cherries producing the disease called "yellows" or "shot- 

 hole." The elongated conidia are formed subepidermally in an acervulus. 

 Later in the summer in the same or other acervuli small almost spherical 

 cells are formed, frequently called microconidia. In the stroma developing 

 below the acervulus Higgins (1914a) and Backus (1934) observed the 

 formation of numerous elongated coiled ascogonia which extend up to 

 the microconidial layer. Backus showed that these microconidia grew 

 fast to the terminal cells of the ascogonium, i.e., to the trichogyne, and 

 should therefore be considered as sperm cells. Subsequently ascogenous 

 hyphae are produced and the apothecium develops. Higgins identified 

 this fungus with the genus Coccomyces but Nannfeldt indicated that 

 this is incorrect. He therefore gave to these forms the name Higginsia. 

 Unfortunately this name is preoccupied and until a valid name is pro- 

 posed the name Coccomyces will probably continue to be used. (Fig. 79.) 

 Family Helotiaceae. Apothecia mostly fleshy, disk- or cup-shaped, 

 at first closed, often stalked, the excipulum consisting of filamentous 

 hyphae, sometimes grading into an outer layer of shorter, thicker cells. 

 Mostly saprophytic or parasitic upon plant tissues. Apothecia not origi- 

 nating in sclerotia. Conidial stages of reproduction usually not present 

 or at least rarely conspicuous. Hdotium produces sessile or almost sessile, 

 disk- or cup-shaped apothecia, small to several millimeters in diameter, on 

 plant parts, probably mostly as saprophytes. The hymenium is often 



