ii THE WEB OF LIFE 31 



The strange inter-relations between plants and animals 

 are again illustrated by the carnivorous, generally in- 

 sectivorous, plants. It is not our business to discuss the 

 original or primary import of the pitchers of pitcher- 

 plants, or of the mobile and sensitive leaves of Venus' 

 Fly-Trap ; nowadays, at any rate, insects are attracted 

 to them, captured by them, and used. Let us take only 

 one case, that of the common Bladderwort (Utricidaria). 

 Many of the leaflets of this plant, which floats in summer 

 in the marsh pond, are modified into little bladders, so 

 fashioned that minute " water-fleas ' -which swarm in 

 every corner of the pool can readily enter them, but 

 can in no wise get out again. The small entrance is 

 guarded by a valve or door, which opens inwards, but 

 allows no egress. The little crustaceans are attracted 



o 



by some mucilage made by the leaves, or sometimes 

 perhaps by sheer curiosity ; they enter and cannot re- 

 turn ; they die, and their debris is absorbed by the 

 leaf. 



Again, in regard to distribution, there are numerous 

 relations between organisms. Spiny fruits like those of 

 Jack-run-the-hedge adhere to animals, and are borne 

 from place to place ; and minute water-plants and 

 animals are carried from one watercourse to another on 

 the muddv feet of birds. From one clodlet from a bird's 



/ 



foot Darwin got eighty seeds to germinate ! Not a bird 

 can fall to the ground and die without sending a throb 

 through a wide circle. 



A conception of these chains or circles of influence is 

 important, not only for the sake of knowledge, but also 

 as a guide in action. Thus, to take only one instance 



/ 



among a hundred, it may seem a far cry from a lady's 

 toilet-table to the African slave-trade, but when we 

 remember the ivory backs of the brushes, and how the 

 slaves were mainly used for transporting the tusks of 

 elephants a doomed race from the interior to the 

 coast, the riddle is read. 



All over a glade or meadow of a summer morning there 

 may be thousands of spider-webs " with dew be-dia- 

 monded," and this is an emblem of the intricacy of the 



