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PLANT MORPHOLOGY 



Fig. 121. Agaricus campestiis, four-fifths natural size. A, mature basidiocarp, showing 

 pileus, stipe, and annulus; B, view of underside of pileus with stipe removed, showing the 

 radiating gills; C, young basidiocarp before the pileus has expanded; D, young basidiocarp 

 cut in half, showing velum attached to stipe. 



opening on its upper side. Ordinarily, however, the basidiocarp is 

 bracket-like or umbrella-like, the tubes opening on its lower side. The 

 texture of the basidiocarp may be leathery, fleshy, or hard and woody. 

 Some of the largest genera are Merulius, Porta, Fomes, Polyporus, Poly- 

 stichuSy and Boletus. Polyporus, the largest genus, has about 500 species. 



