FUNGI CONTINUED; CLASSIFICATION. 217 



3. SUBCLASS ETTASCOMYCETES. 



Asci associated in surfacus forming a hymenium, or in groups or inter- 

 mingled in the elements of a fruit body. Fruit body usually present. 



The following four or five orders comprise the Discumyeetes, according 

 to the usual classification. 



444. Order Protodiscales (Protodiscineae). — The a.sri are exposed and 

 form large and indefinite groujis, but there is no definite fruit bodv. E.x- 

 amples: leaf curl of peach, ]ilum pocket, etc. (E.xoascus). 



445. Order Helvellales (Helvellineaej.— The asci form large fields over 

 the upper portion of the fruit body. This order includes the morels ffig. 

 231a), helvellas, earth tongues (Geogh.issum I, etc. 



446. Order Pezizales (Pezizineae). — The asci form a definite field or 

 friuting surface surrounded on the sides and below bv a wall of fungus tis- 

 sue, forming a fruit body in the shape of a cup. These are known as the 

 cup fungi (Peziza, Lachnca, etc.). 



447. Ord;r Phacidiales (Phacidiinefej. — Fungi mostly saprophytic, and 

 fruit body similar to the cup fungi. Examples: Propolis in rotting wood, 

 Rhytisma forming black crusts on leaves (maple for example), Urnula 

 craterium, a large black beaker-shaped fungus on the ground. 



448. Order Hysterialea (Hysteriinese). — Fungi with a more or less elon- 

 gated fruit body \\-ith an enclosing wall opening by a long slit, ici some 

 forms the fruit body has the apjpearance of a two-lip) perl body; in others 

 it is shaped like a clam shell, the asci being inside. Example, H\"stero- 

 graphium common on dry, dead, decorticated sticks. 



449. Order Tuberales (Tuberineae). — The more or less rounded fruit 

 bodies are usually subterranean. The most important fungi in this order 

 are the truffles (Tuber). The mj'celium of many species assists in the 

 formation of mycorhiza on the roots of oaks, etc., and several species are 

 partly cultivated, or protected, and collected for food. This is especially 

 the case with Tuber brumale and its forms; more than a million franis 

 worth of truffles are sold in France and Italy yearly. Dogs and pigs are 

 employed in the collection of trufiles from the ground. 



450. Order Plectascales (Plectascinese). — The fruit body of these plants 

 is more or less globose, and contains the asci rjistributed irregularh' through 

 the mycelium of the interior. Some are subterranean (Elaphomyces), 

 while others grow in deca^'ing plants, or certain food substances (Euro- 

 tium, Sterigmatocystis, Penicillium). Penicillium in its conidial stage 

 forms blue mold on fruit, bread, etc. 



The following four orders comprise the Pyrenomycetes, according to the 

 usual classification. 



451. Order Perisporiales. — The pio\vder\" milde^^■s are good examples of 

 this order (Uncinula, !Microspha;ra, etc.. Chapter XXI). 



