NUTRITION ' : MUSHROOMS. 



335 



tris) there are a large number of other edible species. But 

 one should be very familiar with any species which is gathered 

 for food, unless collected by one who certainly knows what the 

 plant is, since carelessness in this respect sometimes results fatally 

 from eating poisonous ones. 



618. A plant very similar in structure to the Agaricus campes- 

 tris is the Lepiota naucina, but the spores are white, and thus the 

 gills are white, except that in age they become a dirty pink. 

 This plant occurs in grassy fields and lawns often along with the 



Fig. 442. 



Amanita phalloides ; plant turned to one side, after having been placed in a horizontal 

 position, by the directive force of gravity. 



common mushroom. Great care should be exercised in collect- 

 ing and noting the characters of these plants, for a very deadly 

 poisonous species, the deadly amanita (Amanita phalloides) is 

 perfectly white, has white spores, a ring, and grows usually in 

 wooded places, but also sometimes occurs in the margins of lawns. 

 In this plant the base of the stem is seated in a cup-shaped struc- 

 ture, the volva, shown in fig. 441. One should dig up the stem 

 carefully so as not to tear off this volva if it is present, for with 

 the absence of this structure the plant might easily be mistaken 

 for the lepiota, and serious consequences would result, 



