The Breath of a Bird 



185 



millions of one-celled animals! For here before us we 

 have what is almost exactly like the little flowing drops 

 of jelly called Amoebae which we may find in quiet ponds 

 and watch as they move about in search of food ; flowing 

 around a bit of nutriment, digesting it and flowing away 

 from the waste matter which is left. This is just what the 



Fig. 136. — Blood-corpuscles of bird. 



white corpuscles do; they flow around the food which is 

 absorbed by the walls of the digestive canal, and in fact 

 act like tiny independent animals, parts though they are 

 of the great whole. The oval corpuscles carry and dis- 

 tribute the oxygen, and here we have in a sentence the 

 inner living' of a bird: the food-canal bringing in food 

 and preparing it; the windpipe and lungs admitting 



