140 Miss Wheldale, On the nature of anthoci/anin. 



I. White flowers, of which an extract ogives a bright yellow 

 colour with alkalis and acids, a bright yellow precipitate with 

 basic lead acetate and a reaction with iron salts. 



(a) Those giving a green colouration with iron salts : 

 Mesemhryanthenium Haworthii, Golchicum sp., Nerine flexuosa, 

 paper white variety of the polyanthus Narcissus, white berries 

 of Si/mphoricarpus raceniosus, white variety of Chrysanthemum 

 carinatiim, white variety of autumnal cultivated Ghri/santhemum, 

 ivory white variety of Viola tricolor, white variety of Ahutilon 

 striatum, Erica Bowieana and white variety of Primula sinensis. 



{h) Those giving a blue colouration with iron salts : None. 



II. Yellow flowers (albino as regards anthocyanin, but with 

 yellow plastid pigments), of which the extract gives the same 

 reactions as those in I. 



(a) Those giving a green colouration with iron salts: 

 Ivory variety of Helianthemum vulgare, Calendula officinalis, 

 yellow variety of autumnal cultivated Chrysanthemum, Erigeron 

 Canadensis, Gaillardia sp., Gazania splendens, Helenium iiudiflorum, 

 Helianthus annuus, Picris paucifiorus, Senecio Jacohaea, pale and 

 deep yellow varieties of Zinnia elegans, Hypericum Hookerianum, 

 Spartium junceum, Linum flavum, Bartonia aurea, yellow variety 

 of Ahutilon striatum, Jasminum nudiflorum, Argenione grandifiora, 

 Eschscholtzia Californica, PHmula Kewensis, Potentilla fruticosa, 

 Hyoscyamus chloranthus, yellow variety of Salpiglossis grandijiora, 

 calyx of Physalis alkekengi, pale and deep yellow varieties of 

 Tropaeolum majus, Tropaeolum canariense, and pale and deep 

 yellow varieties of Viola tricolor. 



(6) Those giviug a blue colouration with iron salts : 

 Alyssura maritimum. 



Exceptions were the following, which give a yellow precipitate 

 with basic lead acetate, a yellow colour with alkalis but not the 

 above reactions with iron salts: Taraxacum officinale^, Brassica 

 sinapis*, Cucurbita Pepo*, and fruit oi Lycopersicum esculentum. 



It might be noted that these exceptions are chiefly plants 

 which do not normally produce anthocyanin. 



The xanthei'c pigments of many yellow flowers seem to be 

 very similar in nature to the substances present in the above 

 Classes I. and II. They differ in that the yellow extract usually 

 deepens to orange-yellow or red with alkalis and acids and the 

 precipitates with basic lead acetate are of corresponding shades. 

 The iron reaction is usually green. Class III. contains genera 

 whose flowers give these reactions. 



* Tested only with ferric chloride which does not always give a satisfactory 

 result. 



