Fig. 29. — Ranunculus aquatiiis. 



CHAPTEE II 



DICOTYLEDONS 



EANUNCULACE^ 



This interesting family consists principally of herbs. 

 Clematis, however, is a woody climber. The group is 

 widely extended in temperate and northern regions, but 

 except on the highlands is almost completely absent 

 from the Tropics. Clematis, however, and an allied 

 genus extend into sub-tropical or even tropical districts. 



The embryo is generally minute ; it is so in all the 

 British species. The petals are sometimes small or 

 absent, in which cases the sepals are often white or 

 coloured (Clematis, Anemone, Caltha, TroUius, Eranthis, 

 Aconitum), generally white or yellow, but sometimes 

 red, blue, or violet. Honey is often absent (Clematis, 

 Thalictrum, Anemone, Adonis), and insects come for the 

 pollen only. The nectaries are sometimes on the ovary 

 (Caltha), sometimes on the stamens (some Anemones), 

 often on the petals (Ranunculus, Helleborus, Trollius, 

 Aquilegia, Aconitum, etc.), rarely on the sepals (some 

 Pseonies). 



In Thalictrum the achenes are ribbed, in Eanun- 

 culus they are wrinkled (water forms) or smooth, in 



47 



