640 The Outline of Science 



chlorophyll; the brighter tints are due to the presence of 

 special pigments, which are by-products or waste-products 

 of the leaf's intense life. 



Finally, the leaves fall gently from the trees, or, after 

 writhing and rustling in the wind, as if loath to be separated, 

 are violently wrenched off and whirled along the ground. 

 But the tree is not really impoverished by the yearly loss 

 of its leaves, while they, on the other hand, weathered, faded 

 and torn, and mouldered by fungi, are buried by earth- 

 worms, to form, with the help of bacteria, the vegetable 

 mould in which are cradled the seedlings of another year. 



BIBLIOGRAPHY 



BOSE, Life Movements in Plants. 



BOWER, Botany of the Living Plant and Plant Life on Land. 



DARWIN, Insectivorous Plants and Movements and Habits of Climbing Plants, 



FARMER, Plant Life. 



GEDDES, Chapters in Modern Botany. 



HARVEY-GIBSON, Outlines of the History of Botany. 



HERRICK, Wonders of Plant Life. 



JONES AND RAYNER, Plant Biology. 



KERNER AND OLIVER, Natural History of Plants. 



MULLER, Fertilisation of Flowers (translated by D'ARCY THOMPSON). 



SCOTT, Evolution of Plants. 



TIMIRIAZEFF, The Life of the Plant. 



