32 THE COLOURS OF FLOWERS. 



There is one small set of rosaceous plants which 

 exhibit green flowers, such as the genera Alchemilla 

 and Poterium. When we come to consider the sub- 

 ject of degeneration, however, we shall see that these 

 are not really primitive blossoms, but very degraded 

 and altered types. For the present, it must suffice to 

 point out that they have lost some of their sepals, all 

 their petals, and many of their carpels ; and that they 

 cannot therefore be regarded in any way as represen- 

 tatives of the central primordial stock from which the 

 roses are originally derived. This place certainly 

 belongs rather to Potentilla, Agrimoma, and some 

 allied exotic types, with simple regular yellow 

 blossoms. 



Even more primitive in type than the Rosacecz are 

 the lowest members of the Ranunculacece, or buttercup 

 family, which perhaps best of all preserve for us the 

 original features of the early dicotyledonous flowers. 

 The family is also more interesting than that of the roses 

 because it contains greater diversities of development, 

 and accordingly covers a wider range of colour, its 

 petals varying from yellow to every shade of crimson, 

 purple, and blue. The simplest and least differentiated 

 members of the group are the common meadow butter- 

 cups (Fig. 9), forming the genus Ranunculus, which, as 

 everybody knows, have five open petals of a brilliant 

 golden hue. Nowhere else is the exact accordance in 

 tint between stamens and petals more noticeable 

 than in these flowers. The colour of the filaments 

 is exactly the same as that of the petals ; and the 

 latter are simply the former a little expanded and 

 deprived of their anthers. We have several English 

 meadow species, all with separate carpels, and all very 



