FUNGI. 287 
savoury meat-like taste which others of them afford. 
Of all known bodies nitrogen is the most unstable. 
Its compounds are decomposed by slight causes ; 
and therefore its presence in the animal frame is 
the cause of its activity and proneness to change. 
To this circumstance also is owing the fugacious 
character of fungi, their speedy growth and decay. 
Unlike other vegetables, fungi possess the remark- 
able property of exhaling hydrogen gas; and the 
great majority of species, like animals,. absorb 
oxygen from the atmosphere, and disengage in 
return from their surface a large quantity of car- 
bonic acid. By chemical analysis, they are found 
to contain besides sugar, gum, and resin, a yellow 
spirit like hartshorn, a yellow empyreumatic oil, 
and a dry, volatile, crystalline salt, so that their 
nature is eminently alkaline, like animal sub- 
stances extremely prone to corruption. The 
cream-like substance of which the family of Myxo- 
gastres is composed resembles sarcode, and ex- 
hibits Amoeba-like movements. Some of them 
contain such a quantity of carbonate of lime, that 
a strong effervescence takes place on the applica- 
tion of sulphuric acid. Fungi feed like animals 
upon organic compounds elaborated by other 
plants. They contribute in no way as vegetables 
to the balance of organic nature. 
Another property they possess, which connects 
