34 THE HISTOLOGICAL DISTRIBUTION [CH. 



Lupinus grandiflorus \ 



L. perennis hydrochloric acid. 



L. polyphyllus 



Anthyllis Vulneraria caustic potash. 



Begonia acanthostigma alkalies ? 



Gentiana alba hydrochloric acid. 



Scopolia orientalis sulphuric acid. 



Sciadocalyx I/nciani sulphuric acid. 



Strobilanlhes Diirianus alcohol, sulphuric acid. 



S. Sabinianus- alcohol. 



Justicia formosa ? 



Filtonia Pearcei alcohol. 



There has been much doubt in some cases as to whether the coloured 

 deposits are of pigment only, or of other substances such as proteins, 

 tannins, etc., impregnated with pigment. Very beautiful crystals are 

 figured by Molisch (104) from cells of red Cabbage leaves and leaves of 

 Begonia maculata. Molisch notes that a low temperature induces the 

 formation of the crystals which may disappear at higher temperatures. 

 In Brassica and Begonia, appearances are certainly in favour of the 

 crystals being pigment. In other plants where the solid deposit is in 

 the form of coloured spheroids or globules, the latter often being viscous 

 in consistency, it seems more probable that the matrix of the bodies 

 is of a tannin or protein nature, and has become impregnated with 

 pigment. 



Gertz maintains several possibilities for the natural occurrence of 

 anthocyanin in cells. (1) In crystals as mentioned above either of 

 pure anthocyanin or of colourless substances infiltrated with anthocyanin. 

 (2) In very young cells containing several vacuoles, anthocyanin in 

 the vacuoles may appear as red or blue globules having a superficial 

 likeness to anthocyanin bodies. (3) Anthocyanin may occur in amor- 

 phous or globular form, or bound up with amorphous or globular bodies 

 which are of a different nature from the pigment. 



To demonstrate how solid anthocyanin bodies may arise, Gertz 

 describes two examples of what may happen artificially in the cell. 

 If tissues of Slrobilanthes Diirianus be placed in alcohol, coloured drops 

 appear which afterwards disappear again. The explanation offered is 

 that the alcohol first causes the cells to plasmolyse, and substances in 

 the cell may be precipitated and take up anthocyanin. Later, when 

 semipermeability ceases, the alcohol redissolves out the pigment. 

 Secondly, in Scopolia orientalis, on addition of sulphuric acid, there 

 is a precipitation of coloured bodies which does not disappear. In this 



