190 



COLOURS OF FLOWERS AS A MEANS OF ATTRACTING ANIMALS. 



In all these instances the stigmas and stamens stand out from the petals, but it 

 may liappen that the floral-leaves themselves are thus rendered conspicuous by 

 a contrast of colours, as, for exanjple, in the flowers of Victoria regia, whose 

 outer petals are white, ?.nd the inner crimson. In Papilionaceous flowers it is often 

 observed that the upwardly curved petal called the standard is coloured difierently 

 from the keel and the wings. The Vetches and Peas (Vicia picta, Lathyrus 

 odoratus, Baptisia australis) may be quoted as examples. Those Papilionaceous 

 flowers are most remarkable in which the two lateral wings are dark violet or 



almost black, and look like two dark eyes 

 below the yellow standard (e.g. in Vicia 

 Barbazetce, Melanops, and Faba; see fig. 254). 

 In thousands of flowers the petals are 

 marked with spots, speckles, stripes, bands, 

 and borders, the contrasting colours being 

 set next one another. The white perianth- 

 leaves of the Snowflake (Leucojum vernum; 

 cf. fig. 244) have a green spot near the 

 apex; the scarlet-red standard of the butter- 

 fly-corolla of Clianthus Dampieri carries 

 a dark- violet eye-spot in the centre; the 

 orange tongue-shaped flowers of Gorteria 

 ringens have a black spot at the base, in 

 which are scattered white stripes and dots; 

 the delicate perianths of Sisyrinchium 

 anceps are blue or violet above, but yellow 

 or orange below. The white coronas of the 

 Narcissus (Narcissus poeticus; cf. fig. 255) 

 are surrounded by a cinnabar-red border; 

 and in the blue flowers of the Forget-me- 

 not (Myosotis), the mouth of the short tube 

 has an irregular yellow ring round it. Those plants which have been called 

 "tricolor" on account of the various tints of their flowers, e.g. the three-coloured 

 Bindweed (Convolvulus tricolor), the Pansy ( Viola tricolor), and the three-coloured 

 Vetch (Vicia tricolor), may also be quoted as examples. 



Sometimes the spots, points, and stripes standing up from the ground-colour of 

 the flowers perform the double function of showing the entrance to the honey 

 easiest for the approaching insects, and at the same time most advantageous to the 

 plant itself. Of this we shall speak more particularly later on. But it would be 

 too much to say that all spots are to be regarded as signals or to call them " honey- 

 indicators " or " path-finders ". They are found often enough in flowers from 

 which honey is altogether absent, as, for example, in those of Hibiscus Trionum, 

 and of the opium and common red Poppies (Papaver somniferum and Rhceas), 

 where their only use can be to show up the flowers. It should be noted here that 



Fig. 255.— Narcissus (Narcissus poeticus); the Corona in 

 the centre of the flower is fringed with a cinnabar- 

 red border (black in the figure). 



