264 FUNGI. 



perpendicular to the vertical plate, each of which bears 

 four very minute stalked spores upon its apex. No mode 

 of true sexual reproduction has been clearly observed in 

 Mushroom and its allies. Other Fungi depart very widely 



FIG. 205. Mushroom (Agaricus). 



from this Type, but all agree in the absence of green- 

 colouring matter and of starch in their cells, and in their 

 consequent dependence upon decaying animal or vege- 

 table matter for support. They are mostly short-lived, 

 and often deliquesce when mature, though some, as the 

 Touch-woods, are hard, woody, and persistent. 



Other Fungi present no distinction of stem and pileus, 

 and the spore-bearing cells clothe excavations in the 

 cellular substance of the Fungus (as in Puff-balls), or 

 the spores may originate by free cell-formation, 2, 4, or 

 more together, in the interior of certain terminal tubular 

 often clavate cells, called asci, as in the subterranean 

 esculent fungus called Truffle (Tuber cibarium} in Peziza 

 and generally throughout the great group deriving its 

 appellation from this mode of asexual origin of the 

 spores in an ascus (Ascomycetes). 



The variety in arrangement and structure of the asexual 

 reproductive system of the Fungi is extreme, and in a 



