FORM AND CHARACTKRS ' )]■ THI- Wl S1IR< )( )M. 



3 



Parts F'resent in Other Mushrooms — The Volva. — Some otht-r iiiush- 

 rooms, like the di-aii/v Anuiiiihi {Aiiiaiiila phatloiJes) and other species 

 of the genus Amanihi, have, in addition to the cap, gills, stem, and 

 ring, a more or less well formed cup-liUc striKturc attacht-d to the 

 lower end of the stem, and from which tht- stem appears to spring. 

 (Figs. 55, 72, etc.) This is the volva, sometimes popularly called 

 the "death cup," or "poison cup." This structure is a very 

 important one to observe, though its presence hy no means indicates 

 in all cases that the plant is poisonous. It will he described more in 

 detail in treating of 

 the genus Amanita, 

 where the illustra- 

 tions should also be 

 consulted. 



Presence or Absence 

 of Ring or Volva. — 

 Of the mushrooms 

 which have stems 

 there are four types 

 with respect to the 

 presence or absence 

 of the ring and 

 volva. In the first 

 type both the ring 

 and volva are ab- 

 sent, as in the 

 common fairy ring 

 mushroom, Maras- 

 mius oreadcs; in 

 the genus Lactariits, 

 Knssula, Tricbolo- 

 ma, Clitocvbc, and 

 others. In the second type the ring is present while the \-olva is 

 absent, as in the common mushroom, Agaricns campcstris, and its 

 close allies; in the genus L'piota, Armil/aria, and others. In the 

 third type the volva is present, but the ring is absent, as in the 

 genus l^o/varia, or Amanitopsis. In the fourth t\-pe both the ring 

 and volva are present, as in the nenu^ Amaiiifii. 



The Stem is Absent in Some Mushrooms. — There are also quite a 

 large number of mushrooms which lack a stem. These usually 

 grow on stumps, logs, or tree trunks, etc., and one side of the cap 

 is attached directly to the wood on which the fungus is growing. 



?"icuTKF. 2. — Agaricus campestris. "Buttons" just appearing 

 through the sod. Some spawn at the left lower corner. Soil 

 removed from ihe front. (Natural size.) 



