72 THE COLOURS OF FLOWERS. 



especially in the simpler orders. Erysimum orientale 

 varies from white to pale primrose. RapJianus ra- 

 phanistnim, as already noted, is usually even lilac, 

 often white, and on the sea-shore yellow. The 

 white cistuses often revert to a pale sallow tinge. In 

 some roses, the throat becomes yellow in certain 

 specimens. Many umbcllates vary from white to a 

 faint yellowish green. In several other cases, stray 

 yellow specimens of normally white species are not 

 uncommon. 



Pink and red flowers almost invariably revert in 

 many individuals to white. Indeed, there is probably 

 not a single blossom of these colours in England of 

 which white specimens may not occasionally be 

 gathered. A few typical instances must suffice. All 

 the British roses are reddish pink or white. So are 

 Saponaria officinalis^ and many pinks. Malva moscJiata 

 runs from rose-coloured to white ; M. rotundifolia from 

 pale lilac-pink to whitish, Erodiiim cicutarinin has 

 rosy or white petals ; all the geraniums occasionally 

 produce very pale flowers. White varieties of heaths 

 are frequent in the wild state. Where the red or 

 purple is very deeply engrained, however, as in 

 labiates, reversion to white occurs less commonly. 

 But almost all pink or red flowers become white with 

 the greatest readiness under cultivation. 



Blue flowers in nearly every case produce abundant 

 red, pink, and white varieties in a state of nature. It 

 would seem, indeed, as though this highest develop- 

 ment of colour had not yet had time thoroughly to 

 fix itself in the constitution of most species. In an 

 immense number of cases, it still appears as a late 

 modification of red, the bud or young petals being 



