397 



THE CHEMISTRY OF SOME COMMON PLANTS. 



p. Q. KEEGAN, LL.D., 

 Patterdale, Westmorland. 



Fly Agaric {Amanita jnuscaria). — In birch woods perched on 

 turfy, non-calcareous soil, this mushroom makes a grand show 

 by virtue of its bright scarlet cap studded with whitish warts, 

 and its white-frilled collar. Its rather potent physiological 

 effects have occasioned a considerable amovmt of chemical 

 investigation as to the nature of its constituents. It has been 

 employed variously as an insect poison, an intoxicant of the 

 genus Homo, and a cure for epilepsy. Dried in air the plant 

 yields 14.9 per cent, solid matter and 1.05 ash ; it contains an 

 oil which on analysis is found to consist of 90 per cent, oleic 

 acid, 7.42 lecithin, and 2.58 glycerine, ergosterine, choline, 

 and butyric and palmitic acids ; a dihexon sugar (trehalose 

 C^^H^-O^i) is also found, but no mannite or glycogen ; chitin 

 takes the part 01" the cellulose of ordinary plants, and therewith 

 is connected an anhydride of glucose in place of lignin. The 

 most potent and interesting of the constituents, however, are 

 those which are the result of the disorganisation (hydration) of 

 the albumenoids. A necrobiotic product, a ptomaine called 

 muscarine C'H^^NO- is found to the amount of 15 per cent, 

 of the fresh plant, and seems to exist in greatest and most 

 virulent amount during the period after the ripening of the 

 spores, i.e. practically when the fungus has begun to decay. 

 It is essentially a narcotic or nerve poison. Physiological 

 experiments prove that it lessens or abolishes the action-current 

 of nerve and induces diastole arrest of the heart, but it does not 

 violently attack the mucous membrane of the digestive passage, 

 nor paralyse the muscles or give myosis ; it, however, seriously 

 disturbs the nervous system with a tendency to bring on 

 insensibility and torpor. There is also a second poison, a kind 

 of soluble ferment which diminishes in quantity when the plant 

 is dried, and is quite decomposed and rendered inert at 100° 

 temp. Proteolytic enzymes analogous to enterokinase which 

 rapidly digest albumen, and an erepsin which destroys and 

 transforms peptone and albumoses with very great activity 

 have also been indicated by physiological experiment. There is 

 no laccase in the plant. The scarlet glories of the pileus are not 

 due to carotin or tannin, but to the oxidative action of its 

 tissues on the nuclear matter (nucleo-proteid and its decomposi- 

 tion products) distributed therein ; the nucleic acid is decomposed 

 and purine bases (xanthin, &c.) are liberated like what occurs in 



J906 November i. 



