230 Keegan : The Chemistry of Some Common Plants. 



and wax may be extracted from the dried substance and some 

 free phlorogflucin apparently, but no starch, sugar, or alkaloid 

 is detectable ; the fresh leaves yield i'i2 per cent, of ash rich in 

 alkaline salts, in phosphorus (over 4 per cent.) and in sulphur, 

 but poor in lime and silica. The flowers present the rare com- 

 bination of richness and purity of tint with power and sweetness 

 of scent. It is extremely difficult to determine precisely what 

 the chromogen of the pig"ment really is, but that it is extremely 

 sparse and exceeding-ly powerful there is not the slightest doubt, 

 also that the particular period of the year and the shady covert 

 wherein the efflorescence bursts into full expansion are agencies 

 operative in the case. The ash of the flowers contains 44*7 

 per cent, soluble salts, 10 lime, i6*6 P'O', and 5*4 SO''. The 

 whole plant is extremely rich in potass, soda, phosphorus, and 

 chlorine, although no starch is ever produced in the leaves, 

 the carbohydrate constituent of the mucilage being apparently 

 the chief product of assimilation. 



Dock. Rumex obtusifolius. This is a very familiar 

 wayside plant, conspicuous by reason of its almost tropically- 

 developed leaves. Its chemical development harmonises there- 

 with ; it is eminently pronounced. The root is a veritable 

 storehouse of constituents, its tissues readily responding to the 

 usual tests for starch, mucilage, resin, tannin, phloroglucin, etc. 

 The tannin is iron-blueings, phlobaphenic, precipitates gelatine 

 and bromine water, but not tartar-emetic, and yields on potass- 

 fusion protocatechuic acid and phloroglucin. A special feature 

 of the root which causes it to turn bright yellow (like medicinal 

 rhubarb) when freshly cut is the presence of various derivatives 

 of anthraquinone, viz., chrysophanic acid, nepodin and lapodin, 

 all allied to alkannin, madder dye, etc., and like these yielding 

 beautiful red colours in contact with alkalies. The leaves 

 about 1st August contain much carotin and wax, but little 

 or no fat or resin, also quercetin and tannin, free phloroglucin, 

 very much pectosic mucilage, some starch and levulose (free or 

 as inulin), very little proteid, but a copious supply of pectate of 

 calcium and 11 "7 per cent, of ash in dry, holding 43 '4 per cent, 

 soluble salts, 20 lime, 6*3 P^O'"', etc. In certain summers the 

 leaves decay early and assume a very ' loud ' flame of colour due 

 to an admixture of carotin and ordinary erythrophyll. Altogether 

 it is clear that in this plant the process of deassimilation is very 

 advanced, and high hydrocarbon residues are produced which in 

 these climes are uncommon and inexplicable save by cousinship 

 with tropical outgrowths. 



Figwort. Scrophularia nodosa. The floral parts of this 

 organism present an extraordinary aspect and the plant itself 



Naturalist, 



