THE FORMATION 



OF 



VEGETABLE MOULD, 



THROUGH THE 



ACTION OF WOEMS, 



WITH 



OBSERVATIONS ON THEIR HABITS. 



BY CHAELES DAEWIN, LL.D,, F.E.S. 



THIRTEENTH THOUSAND. 



WITH ILLUSTRATIONS. 



LONDON: 

 JOHN MUREAY, ALBEMAELE STEEET.. 



1897. 



