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or carrots. Mushrooms also contain a little fat, some sugar and 

 phosphate, but as a whole they are to be considered vegetables 

 of a low order and not as good as peas and beans or meat. We 

 must remember, however, that it is perfectly absurd to measure 

 the value of a particular food in terms of calories. 



2. Spoiled Mushrooms. — If a perfectly edible form of mush- 

 room is too old when gathered and especially if it is spoiled, 

 softened, withered, stale or badly canned, changes may occur in 

 its composition which render it unfit to eat. The symptoms of 

 nausea, vomiting, headache, fever of 102 or pulse of 126 appear in 

 one or two hours; to these is soon added a severe diarrhoea. The 

 symptoms subside within a week without fatalities. 



Mushrooms are also very early invaded by insects. These 

 may be inoffensive but they are certainly not aesthetic. Some 

 larvae, however, are poisonous and it is well to reject from your 

 basket all mushrooms which are the feeding ground for small 

 "worms." If the mushroom becomes softened and slimy we 

 may assume that like putrid meat it is infected by microbes. 

 These microbes produce a ptomaine called choline (C2H4OHN- 

 (CH3)30H) which is also found in putrid meat. If this product, 

 choline, is oxidized it becomes muscarine, the active poison of the 

 "fly agaric" {Amanita muscaria) and other mushrooms. Choline 

 and muscarine produce symptoms like cholera and may cause 

 death. 



3. True Mushroom Poisoning (poisoning from mushrooms due 

 to a true poison contained in certain species). — It is an interesting 

 fact that the most dangerous mushrooms are also the most per- 

 fectly evolved ones and are those which the botanist places at 

 the head of his mushroom classification. There are more than 

 1,000 described varieties of mushrooms and of these there are 

 only relatively few which if eaten are poisonous. The Depart- 

 ment of Agriculture lists 72 varieties as "poisonous or suspected 

 of being poisonous," while Dr. Murrill would reduce the number 

 to between twenty and twenty-five varieties. To prevent poison- 

 ing by eating mushrooms there are two principles upon which to 

 work; either be able to identif}' the poisonous ones surely or else 

 learn to identify a few forms of edible mushrooms which do not 



