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TEXTBOOK OF BOTANY 



A related species is the fly mushroom (Fig. 38), which also 

 has a hanging ring, a cup, and white gills and spores ; but 

 its cap is red on top with some scattered white scales. 

 This mushroom grows alone or in groups, in woods of the 

 most varied sorts. Both of these latter species are so poison- 

 ous that 50 grams (less than two ounces) of their flesh is a 

 fatal dose. 



Only one who is thoroughly familiar with mushrooms can 

 be sure of distinguishing the edible from the poisonous 

 species. The only safe plan, if one is to eat mushrooms at 

 all, is to become acquainted with a few forms that cannot be 

 mistaken, and to eat no others except upon the advice of an 



expert. The food 

 value of mushrooms 

 is small at best, and 

 it is not worth while 

 to run the slightest 

 risk of what may 

 prove a serious mis- 

 take. No fungus 

 should ever be eaten 

 unless it is young and 

 fresh and shows no 

 traces of being de- 

 cayed or worm-eaten. 

 110. "Fairy Rings." 

 These more or less 

 regular circles of fruit- 

 ing bodies, growing in 

 lawns or pastures, are 

 produced by certain 

 species of mushrooms. 



The ring-like arrangement of the fruiting bodies results from 

 the growth of the vegetative threads within the soil year 

 after year. At first a small area of the soil is penetrated 



FIG. 39. An edible mushroom (Hygrophorus 

 virgineus). Photograph by E. T. Harper. 



