400 Keegan : The Chemistry of some Common Plants. 



oxalate of calcium ; the starch, which is abundant in the fresh 

 leaf, disappears on drying" and subsequent treatment with 

 benzine, alcohol, etc. ; the ash amounts to 14.9 per cent, in 

 dry and contains 61.9 per cent, soluble salts, 6.3 silica, 12.2 lime, 

 3.4 magnesia, 4.2 P^O^, 4.3 SO^, and 17.2 chlorine ; the larger 

 leaves gathered a little later, showed in their ash 57 per cent, 

 soluble salts, and 14.6 chlorine. The floral parts yield 1.7 per 

 cent, wax and carotin (occurs in homogenous plastids at the 

 base of the petal), some resin, but no fat-oil apparently ; the 

 yellow colour of the upper petal is due to quercetin ; there is 

 also an iron-greening tannin which precipitates gelatine and 

 bromine water, some free phloroglucin, glucose, and cyclamin, 

 a large quantity of easily coagulable mucilage, some oxalate 

 of calcium, and traces of starch. The highly remarkable fact 

 here is the concentration of tannic matters in the flowers, there 

 being practically none in either leaves or roots ; and moreover, 

 this accumulation is, or rather ought to be, as it were a power- 

 ful one as regards chromogenic effects, inasmuch as it is difficult 

 to assign the cause why the Primrose petal should not be a deep 

 pure pink, or even a nearly pure blue. No doubt, however, it is 

 the rapidity with which the blossoms evolve (aided greatly by the 

 starch-packed rhizome and roots) that does not allow of sufficient 

 time for the tannic chromogen to develop into coloured pigment. 

 Cowberry iyVaccinium vitis idcea). — Of all the moimtain 

 dwellers this one is possessed of sufficient vitality to enable it to 

 keep its leaves during the winter rigour, their natural green too, 

 remaining all the while. The comparative scarcity of the plant 

 however, forbids any detailed analysis. The leaves, however, 

 may detain our attention for a few moments. They are provided 

 with a strong cuticle, the cells of the upper epidermis are thick- 

 walled, as are also all the cell-walls of the mesophyll, while the 

 edges of the leaf are strengthened by layers of fibrous scleren- 

 chyma. The whole of their nitrogenous matter in September 

 is in the form of albumenoid ; there is a large quantity of quinic 

 acid, and much free quinol according to Kanger ; the tannin 

 is C'^*' H^** O^" which on potass-fusion yields quinol ; also a 

 considerable quantity of a resinous glucoside called ericolin, 

 which, like most such bodies, is of doubtful definite chemical 

 individuality ; as well as a bitter principle, likewise ill-defined, 

 named ericolin, which is inodorous, but on decomposition by dilute 

 acids readily yields a volatile product with a characteristic odour. 

 Other authors have detected free phloroglucin in the Ericales, but 

 the presence of quinol is more probable and of great interest. 



Naturalist, 



