HYBRIDISING AND CROSS-BREEDING. 125 



shaped deep yellou' cup about an inch in length, while the cup 

 of the Poets' Narcissus is flat or shallow, yellow also, but having 

 a reddish-purple ring round its margin ; and in the hybrid 

 resulting from these two species, we find the margin of the 

 yellow cup suffused with deep orange, which is just the colour 

 obtained when we mix reddish purple and deep yellow on the 

 palette. The Poets' Narcissus crosses freely with some forms 

 of the Polyanthus Narcissus (N. Tazetta), even in a state of 

 nature ; and by crossing it with some of the pure white varie- 

 ties, as N. Tazetta papyracea, it is not improbable that rosy or 

 lilac cupped varieties might be obtained. From the above 

 facts it is evident that in some cases the colours of varieties or 

 species, when crossed, are mixed or blended just in proportion 

 to the elective affinity or sexual vigour of either parent, which, 

 indeed, often varies in each seedling or individual produced ; 

 while in other cases one colour only predominates in the 

 flower, the other being rendered latent, or perhaps attracted to 

 some other part of the plant (see Datura). This latter kind of 

 colour variation points to the manner in which " blue Roses," 

 " blue Dahlias," and " blue Pelargoniums " will be originated, 

 if such a consummation is ever effected at all. In all these 

 flowers a certain amount of blue is present, but mixed with red 

 in various proportions, the result being lilac or purplish flowers. 

 Now, in order to produce blue flowers, all the red colouring 

 matter must by some means or other be either suppressed 

 entirely, or driven to the stem and leaves, for so long as it 

 retains a place in the flower, it is simply impossible that the 

 flower can be a blue one. Considerable progress has been 

 made in suppressing the red in purple-scarlet Pelargonium 

 flowers, and the late Donald Beaton's " Indian yellow " is an 

 example of the suppression of red colouring matter to a certain 

 extent in an orange-scarlet flower. In hybridising such plants 

 as Begonias of the foliage section, or in crossing tricolor 

 Pelargoniums or Caladiums, some curious changes of colour 

 are perceptible. In tricolor Pelargoniums, for example, we 

 have the green colour of the leaf (blue and yellow) separated 

 to some extent, and some of the red colour which normally 

 belongs to the flower is introduced. Now, if the red cells of 

 colouring matter overlie the green parts of the leaf, the result 

 is a brown tint ; while, if they lie over the yellow portions, the 

 red or pink becomes warmed into' scarlet. In some tricolors 

 the silver race the yellow portions of the leaf are replaced 

 by colourless cells i.e., cells containing colourless fluid ; 

 and when the red variegation lies over this part of the leaf, 

 the result is a clear rose or pink hue, changing at once 



