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THE CHEMISTRY OF SOME COMMON PLANTS. 



p. Q. KEEGAN, LL.D., 

 Pattcrdale, Westmorland. 



Hair Moss [Polytrichum commune). — This plant forms tufts 

 and cushions of pure greenery in woods and on open land where 

 the heather grows. The chemistry of mosses as compared with 

 those of ferns and fungi, is decidedly tame and bald — a cir- 

 cumstance that is evidently connected with the structure of 

 their cells, especially of their cell-walls. ^lost, or at least a 

 great deal of their chemical constituents seem to be absorbed, 

 grasped in, or bound up in a very intimate manner with the 

 cellulosic skeleton of the cell. On nth June, a dried gathering 

 of the plant in fruit yielded to boiling benzene about cme per 

 cent, of a white, waxy matter. The alcoholic extract was acid 

 and faintly bitter, and had no tannoid or tannin, it gave a red- 

 brown colour with iron alum, and very small precipitates with 

 bromine water, and with acetate of lead ; also it gave reactions 

 of cane-sugar, while a red-brown substance was extracted by 

 ammonia from the residue insoluble in water, which consisted 

 mainly of a resinous substance dissolving in sulphuric acid, 

 with a brown colour passing to. a splendid violet. There was no 

 extractible proteid or starch ; there was, however, a con- 

 siderable quantity of mucilage taken up M^ dilute caustic soda 

 solution, and a substance soluble in amyl alcohol, which dis- 

 solved brown in sulphuric acid. The ash of the plant was very 

 small in quantity, and contained 41.9 per cent, soluble salts, 

 16.3 silica, 4.5 lime, 11. 4 oxide of iron, 4.9 P-O'"', 3.iS0^, 

 with some manganese. The above analysis recalls that of 

 lichens rather than that of ferns or mushrooms, notwithstanding 

 the total absence of the highly tinctorial lichen acids and high 

 quinone derivatives associated therewith. In fact, it occurred 

 to me during and in view of the analyses that mosses must be 

 a class of plants specially created, so to speak, and absolutely 

 distinct from all other members of the vegetable kingdom. 

 Their cell-wall, as aforesaid, is the chief seat of the chemical 

 constituents. It contains no lignin, but has pectin, and only 

 yields cellulose reactions after boiling with dilute alkali ; hence 

 the soluble carbohydrates are here converted with special 

 facility into insoluble ones, and these again into cellulose. 

 By prolonged boiling under pressure in dilute caustic soda, 

 Czapek obtained a phenolic body, which he named si:)hagnol. 



Naturalist 



