ASCOMYCETES— PE2IZA 



239 



of a true sexual process in the vast majority of cases. Common 

 parasites belonging to this group are the Mildews [Erysiphacea;), 

 the Ergot of Rye {Claviceps purpurea, Fig. 128, A), and the 

 Vegetable Caterpillar [Cordyceps) ; but there are numerous sapro- 

 phytes, such as the ubiquitous Blue Mould [Penicillium), the 

 C u p-fungi 

 (speciesoi Peziza, 

 Fig. 126, C), the 

 Stag's Horn 

 Fungus {Xylaria, 

 Fig. 126, A), the 

 Morel {M or- 

 cliella, Fig. 126, 

 D), and Nedria, 

 which is the 

 cause of the 

 bright red pus- 

 tules so common 

 on decaying 

 branches and 

 sticks. 



A general 

 idea of the As- 

 comycetes can be 

 obtained from an 

 examination of a 

 species of Peziza. 

 The septate my- 

 celium of this 

 Fungus is peren- 

 nial and ramifies 

 in the decaying 

 substratum {e.g. dead trunks and branches, soil rich in humus), 

 its presence only becoming apparent in autumn, when conspicuous, 

 and often brightly coloured, cup-shaped fruit-bodies (apothecia, 

 Fig. 126, C) are produced at the surface. In a vertical section 

 through one of these (Fig. 127, B) the hyphffi are seen to be so 

 densely compacted as to produce a false tissue, the elements of 

 which are quite irregularly arranged, except for those hning the 



Fig. 126. — Fruit-bodies of various Ascomycetes. 



A, Xylaria hypoxylon (Stag's Horn Fungus). 



B, Geoglossum. C, Peziza (Cup-fungus). D, 

 MorclieUa (Morel). E, Sclerotinia, showing 

 apothecia arising from sclerotium. 



