238 



MYCOLOGY 



SO that the food value of this form is less than had formerly been sup- 

 posed. The fatty substances soluble in ether are present to the amount 

 of 4 to 8 per cent. The carbohydrates (cellulose, glycogen, trehalose, 

 mannite, glucose, etc.) make up the largest part of the dry matter of 

 the mushroom. Starch usually present in higher plants is absent in 

 these fungi. The ash varies greatly, varying from i.o8 to 15 per cent. 



with potassium as the most 

 , abundant element. Sulphuric 

 acid occurs in the ash of all fungi, 

 with 1.58 per cent, in the ash of 

 Helvella esculenta. 



The poisonous substances are 

 alkaloids, such as choline, found 

 in Amanita muscaria, Helvella 

 esculenta and other fungi, neurin 

 (deadly), muscarin, the most 

 dangerous alkaloid found in toad- 

 stools, as in Amanita muscaria 

 (Fig. 93). Phallin, a deadly 

 poison, found in Amanita phal- 

 loides, is albuminous in nature. 

 Helvellic acid, a deadly poisonous 

 substance, occurs in Helvella es- 

 culenta, especially in old decaying 

 specimens. The symptoms of 

 poisoning with muscarin are long 

 delayed. They may be summed 

 up in the words of Mr. V. K. 

 Chestnut (Circular No. 13 Divi- 

 sion of Botany, United States 

 Department of Agriculture) : 

 "Vomiting and diarrhoea almost 

 always occur, with a pronounced flow of saliva, suppression of the 

 urine, and various cerebral phenomena beginning with giddiness, 

 loss of confidence in one's ability to make ordinary movements, and 

 derangements of vision. This is succeeded by stupor, cold sweats, 

 and a very marked weakening of the heart's action. In case of rapid 

 recovery, the stupor is short and usually marked with mild delirium. 



Fig. 95. — Deadly araanita, Amanita 

 phalloides, showing death cup, or volva, at 

 base of stipe. (From Gager, after E. M. 

 Kittredge.) 



