ATTRIBUTES OF INANIMATE MATTER. 193 



tive by use, so that the creature can very readily feel 

 its food and then catch it. Of course, its prey is blind, 

 all the cavern's inhabitants being placed upon an 

 equality so far as seeing is concerned. 



Certain animals that live in mud, or alternate be- 

 tween land and water, have two sets of breathing 

 organs, a bronchial and a pulmonary apparatus. The 

 frog in its transition from the tadpole state is tempo- 

 rarily thus ; the mud-fish in the swamps of Southern 

 Australia has gills and lungs, and so does a kindred 

 fish in Africa, and the South American lepidosiren is 

 similarly equipped. These singular creatures show 

 how the forces of organization can adapt themselves 

 to the infringement of circumstances. There is an 

 exhibition of intelligence in the excess and defect of 

 development ; and the most far reaching investigations, 

 fail to reveal whence came this intuitive sense. 



