CHAPTER V: FUNGI WITH GILLS 



GENUS AMANITA 



(Also called Venenarius.) 



THE fungi with gills all have this characteristic in common 

 that they bear their spores on radiating plates or lamellae. Their 

 family name, Agaricacece, is derived from a typical member of the 

 family, Agaricus campestris. The family is the largest and most 

 widely distributed of all the families, and contains some five 

 thousand described species, which are placed in groups or genera, 

 more or less large, based on such characters as the colour of the 

 spores; the position and shape of the lamellae; the colour and 

 texture, as well as the shape, odour, taste, and appendages of the 

 cap and stem. 



The colour of the spores is one of the most important char- 

 acteristics, as the decision as to whether the plant is wholesome 

 or not often rests upon it. The colour may be determined by 

 placing the cap, with spore surface down, on a sheet of white or 

 black paper, and leaving it for a time under an inverted glass, so 

 as to cut off all drafts which may blow the spores away. A print 

 of the radiating gills will then be made in the colour of the spores 

 white, pink, rusty brown, or black. 



For external characters of the stem, one must be careful to 

 get the entire stem from the ground ; for a most important char- 

 acteristic, the volva, if present, will be found at the base. The 

 volva may be membranous and attached to the base, excepting 

 at the rim, or membranous and loose, or present only in the form 

 of rings of scales at the base, with perhaps traces on the surface 

 qf the cap. 



The surface of the stem may be smooth or rusty or mealy 

 white. It may or may not have near the cap a ring of the 

 membrane which covered the gills of the young plant. 



The character of the lamellae and the internal characters of 

 the stem may best be determined by cutting the cap and stem 

 from top to base with a sharp knife, for then it may be seen 

 whether the gills are free from the stem or attached to it, or 



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