ESCULENT FUNGI. 327 



and charcoal. The charcoal contains phosphate of 

 lime, some silica, with traces of phosphate of alu- 

 mina, carbonate of lime, and sulphureted hydrogen. 

 Fungin, obtained from whatever species of fungi, has 

 all these characteristics. This composition shows that 

 it combines the nature of vegetable and of animal 

 matter; and when it is allowed to putrify in water, it 

 has first the odour of putrifying vegetable gluten, and 

 then that of a putrid animal substance. 



Boletic acid crystallizes in irregular white prisms, 

 does not alter when exposed to the air, is soluble in 

 forty- five times its weight of alcohol, or in one hun- 

 dred and eighty times its weight of water, at the 

 temperature of sixty-eight degrees. Its taste is like 

 that of cream of tartar. 



The propagation and growth of the fungi are 

 among the most curious subjects in the economy of 

 nature. Their seeds or germs, too minute in general 

 to be injured by any mechanical, or dissolved by any 

 common chemical, process, remain in the earth or in 

 the substance of vegetables for an unlimited period 

 of time; and they pass through the digestive organs 

 of animals, or endure the action of heat, without sus- 

 taining the smallest injury. This is exemplified in 

 paste made of flour, which produces mould or a spe- 

 cies of fungi, as indeed does almost every vegetable 

 and animal substance when it comes to a certain de- 

 gree of decay, and this developement is only pre- 

 vented by the action of the more active metallic salts. 

 The fungi themselves, when they decay, are, as well 

 as extraneous substances, subject in their turn to the 

 attacks of other fungi. 



Montagu* mentions a case in which the mem- 

 brane that separates the lungs of an animal from the 

 rest of the viscera was covered with blue mould even 



* Ornithological Dictionary, Art. Duck, Scaup. 



