16 The Bible of Nature 



well-burnished bicycles with the extermination of 

 the walrus. As Shelley wrote: 



"Nothing in this world is single; 

 All things by a law Divine 

 In each other's being mingle!" 



Only the working naturalist knows the extent 

 to which living creatures are interlinked in nature. 

 There is a solidarity of kinship, but there is also 

 a solidarity of vital relations. We are familiar 

 with the correlation of organs in the living body, 

 but there is also a correlation of organisms in the 

 web of life. The young of the fresh-water mussel 

 must be nurtured for a time as hangers-on to 

 fishes; there is a fresh- water fish (the bitterling, 

 Rhodeus amarus) whose young must be nurtured 

 for a while inside the gills of the mussel. And 

 this is but an instance among thousands. We re- 

 call a remarkable passage of Locke's : ' This is 

 certain, things, however absolute and entire they 

 seem in themselves, are but retainers to other 

 parts of nature, for that which they are most taken 

 notice of by us. Their observable qualities, 

 actions, and powers are owing to something with- 

 out them; and there is not so complete and per- 

 fect a part that we know of nature, which does not 

 owe the being it has and the excellence of it to its 

 neighbors; and we must not confine our thoughts 

 within the surface of any body, but look a great 



