192 ANTHOCYANINS AND GENETICS 



pigments. Tlie common form of striping is that of anthocyanin on an 

 albino ground, either white (Primula sinensis] or yellow ; the yellow 

 may be a soluble pigment (Antirrhinum majus var. yellow striped 

 crimson), or a plastid pigment (Cheiranthus Cheiri, Tagetes, Tulipa spp.). 

 Less commonly one finds deep anthocyanin stripes on a pale antho- 

 cyanin ground of the same colour (Antirrhinum,, see p. 160), or stripes 

 of one coloured anthocyanin on the ground of another colour, as in the 

 case mentioned by de Vries (565) of Delphinium Consolida striatum 

 plenum in which the flowers may be red striped with blue 1 . Mirabilis 

 Jalapa presents a remarkable series of striped varieties : there may 

 be stripes of magenta (anthocyanin) on a white ground, or of soluble 

 yellow pigment on a white ground, or both magenta and yellow stripes 

 on white (tricolour). Moreover Mirabilis is characterised by a number 

 of heterozygous forms, and we may find a homozygous stripe-colour 

 on a heterozygous ground-colour, for instance, deep yellow stripes on 

 a pale yellow, or orange-red stripes on a magenta-rose ground (Marryat, 

 533). 



Another curious phenomenon is the limitation of striping in most 

 species to one colour, for instance in Antirrhinum the anthocyanin of 

 rose dore and bronze varieties does not occur in stripes, and the 

 same is true of the pale 'tingeing' of anthocyanin. It is only the 

 factor for full colour that is affected by the striped condition. 



With regard to sectorially coloured flowers de Vries (565) notes 

 that they appear to manifest a tendency towards a simple proportion 

 between the two parts. "Frequently exactly half of the flower is 

 atavistic, sometimes a quarter or three quarters. I observed the 

 proportion f in white and red striped tulips and in partially dark blue 

 and partially pale blue flowers of Iris xiphioides, etc." 



The inheritance of striping has received a certain amount of attention. 

 De Vries (565) has investigated the problem in Antirrhinum and other 

 striped flowers. He noted that the striped variety of the larkspur 

 (Delphinium Ajacis and D. Consolida) produces self-coloured flowers as 

 well as striped ones; the self-coloured, moreover, may appear on the 

 same racemes as the striped ones, or on different branches, or some 

 seedlings from the same parent may be self-coloured while others are 

 striped. Seeds, on the other hand, of these blue sports give rise again 

 to the striped variety. Such a variety as this Larkspur, de Vries called 

 ' eversporting,' for as he says : " Here the variability is a thing of absolute 

 constancy, while the constancy consists in eternal changes." His more 



1 There is also a tricolour of red, white and blue. 



