THE BUTTERCUP FAMILY, 77 



as do those of leaves which do not happen to catch 

 anything. 



You must make a point of observing everything 

 you read in this book, and make experiments, such 

 as placing a petiole of this plant in contact with a 

 twig, and seeing how it will have become bent after 

 some hours, and finally coiled round it. 



Knowlto'nia. — This genus is peculiar to South 

 Africa. It has five sepals, 00 petals, 00 stamens, and 

 00 carpels, and all free. It differs from all the other 

 genera in its carpels, becoming succulent and juicy, 

 instead of dry achenes. 



Like all the members of this family, it has a more 

 or less poisonous juice, which will raise a blister; 

 hence the commonest of the five known species is 

 called K. vesicato'ria, i.e. " blistering." 



You will now see from the foregoing few facts why 

 these four kinds are called by separate names, as 

 genera. They all agree in the features italicized ; but 

 each differs from the others in certain important 

 particulars. 



Of course each of these genera has several species. 

 Thus Clem'atis has four, Knoidto'nia five, and Ramm'- 

 culus six, in South Africa. 



Besides these three, there is one other genus, 

 Thalic'trum, with two South African species ; but it 

 only occurs in Caffraria and Natal. 



I will suppose that you have examined a plant 



