NATURAL HISTORY — BOTANY. 233 



into a yellow colour, which forms with alumina a beautiful yellow 

 lake, soluble in neu.tral solvents, such as ether, alcohol, bisulphide of 

 carbon. By acting on the solution of this body with acids, especially 

 hydrochloric acid, it was transformed into the original green. Now, 

 assuming that the green thus formed was composed of blue and 

 yellow colouring matters, the point was to separate these two bodies 

 at the moment of their formation. This must be done by the simul- 

 taneous use of solvents which act differently on the two colouring 

 matters. Such a solvent is a mixture of hydrochloric acid and ether ; 

 and it was used as follows : — 



Two parts of ether and one part of hydrochloric acid, diluted with 

 a little water, were shaken in a stoppered bottle for some time, so as 

 to saturate the ether with hydrochloric acid. When the solution 

 formed by the decolorization of the chlorophyll by bases was shaken 

 with this solution, a remarkable change took place ; the ether re- 

 tained the yellow matter, and the hydrochloric acid the blue colouring 

 principle. The two colours were thus isolated ; but if now alcohol 

 in excess was added, which dissolves both the yellow and green 

 colouring matters and their solvents, the solution became of the 

 original green tint. 



To the yellow matter soluble in ether, Fremy gives the name 

 phylloxanthine, and to the blue colouring matter the name phyllo- 

 cyanine. To the other yellow body which results from the change 

 of phyllocyanine, he gives the name pltylloxantheine. 



The blue and yellow colouring matters may be obtained directly 

 from chlorophyll by adding the ether and acid mixture directly to 

 the alcoholic extract of the leaves. The green first becomes brown, 

 and is then resolved into phyllocyanine, which dissolves in the acid, 

 and phylloxanthine, which dissolves in the ether. This interesting 

 experiment may also be made directly with the leaves. 



Fremy found that the yellow colouring matter formed in the 

 young shoots is the same as that resulting from the decomposition of 

 chlorophyll. It may be extracted by alcohol, and partialiy resolved 

 into yellow and a little blue colour by means of hydrochloric acid 

 and ether. Leaves which become yellow in autumn, then only con- 

 tain phylloxanthine. — -Comptes Rtndus ; Pltilos. Mar/., No. 131. 



RELATIONS OF PLANTS. 



Mr. Maxwell Masters has read at the Royal Institution a paper 

 " On the Relation between the Abnormal and Normal Relations of 

 Plants." The object of the lecturer was to show the difficulty, and 

 in many cases the impossibility, of drawing any definite line between 

 what is considered to be natural and what unnatural in plants. 

 These difficulties depend on many circumstances, among which are — 

 the very great powers of variation naturally possessed by plants ; 

 the fact that a condition which is not unnatural or unusual in one 

 species is the common condition in another ; that irregularity of 

 growth is by no means an abnormal condition ; that a change may 

 be abnormal in a physiological point of view, and may, nevertheless, 

 be quite consistent with the assumed laws of morphology, &c. Nu- 



