OF SOME EDIBLE AMERICAN FUNGI. 157 



Crude Fiber. Under this name is included the residue 

 resistant to boiling acids and alkalis, and scarcely to be con- 

 sidered as homogeneous in nature. The results of the analy- 

 ses are tabulated below. 



It has already been pointed out that the cellulose of the 

 fungi contains nitrogen in many instances, and Winterstein * 

 has shown that the latter is not due to proteids or nucleins 

 mechanically included ; the nitrogen probably belongs to the 

 " cellulose " itself. All attempts to separate the nitrogenous 

 constituent from the portion which yields sugar on hydroly- 

 sis have failed. 



CEUDE FIBER. 



Soluble Carbohydrates. A considerable portion of the 

 solids of the mushrooms is made up of soluble carbohydrates, 

 while starch is ordinarily not found. Trehalose, a carbohy- 

 drate of the formula C^H^On, and resembling maltose in 

 some respects, has been isolated from a number of species ; f 

 and in an extensive series of investigations Bourquelot $ has 

 described a number of carbohydrates including mannite. 



In order to get some idea of the amount of soluble carbo- 

 hydrates present a number of experiments were carried out 

 in the manner described under the methods of analysis. Since 

 trehalose, for example, cannot be quantitatively converted 



* Winterstein, Berichte d. deutsch. chem. Gesellsch., xxviii, p. 167; 

 Zeitschr. fur physiol. Chemie, 1894, xxix, p. 521. 



t Winterstein, Zeitschr. fur physiol. Chemie, 1894, xix, p. 70. The refer- 

 ences to earlier literature are given. 



t These investigations were published in a series of papers in the Comptes 

 Rendus and other scientific journals. 



