Chap. IV.] SUMMARY. 105 



occasionally see an animal like the Ornithorhynchus or Lepidosiren, 

 which in some small degree connects by its affinities two large 

 branches of life, and which has apparently been saved from fatal 

 competition by having inhabited a protected station. As buds give 

 rise by growth to fresh buds, and these, if vigorous, branch out and 

 overtop on all sides many a feebler branch, so by generation I 

 believe it has been with the great Tree of Life, which fills with its 

 dead and broken branches the crust of the earth, and covers tho 

 surface with its ever-branching and beautiful ramifications. 



