ii2 THE COLOURS OF FLOWERS. 



ably in Peperomia, Echeveria, Epipkyllum, and other 

 exotics. The calyx and the expanded stipules which 

 cover the young flower- heads in red clover (Trifolium 

 pratense] and many other clovers, are delicately pink 

 or purple. In T. arvense the sepals are pale lilac, 

 and in T. incarnatum pale yellow. The whole upper 

 portion of the flowering stem in Chrysosplenium is 

 bright golden. 



Where the calyx is largely exposed to view, as in 

 the globe-flower (Trollius), the columbine, the helle- 

 bores, and the monkshood, it is apt to become quite 

 as brilliant as the petals. In such cases its coloura- 

 tion usually follows the same law of progressive 

 development as the corolla. Sometimes, under these 

 circumstances, the now almost useless petals are 

 suppressed altogether, as in Caltka, a near relative 

 of Trollius, as well as in the Anemones and Clematis. 

 At other times they are utilised as nectaries, as 

 in columbine, hellebore, and monkshood. In the 

 meadow-rues (Thalictmm) the petals are suppressed, 

 and the sepals very small, so that the flower depends 

 for attractiveness almost entirely upon its clustered 

 yellow stamens. In Impatiens, Polygala, and some 

 other British genera, sepals and petals share almost 

 equally in the attractive display. 



Where the petals have become much dwarfed, the 

 calyx is apt to aid them, if brilliant colouration again 

 becomes necessary. For example, our own wild 

 gooseberry, wild currant, and most other members 

 of the Ribes genus, have very inconspicuous petals ; 

 but in the North American scarlet Ribes of our 

 gardens {R. sanguineus), the flower has re-assumed a 

 brilliant colouring, and it has done so by making its 



