STUDIES IN ANIMAL LIFE. 



131 



colony has one nutritive fluid 



in common. They are all 



actively engaged in securing 



food, and the labors of each 



enrich all. It is animal so- 



cialism of the purest kind 



there are no rich and no poor, 



neither are there any idlers. 



Formerly the coral -branch 



was regarded as one animal 



an individual; and a tree 



was and is commonly regard- 



ed as one plant an individ- 



ual. But no zoologist now 



is unaware of the fact that 



each polype on the branch is 



a distinct individual, in spite 



of its connections with the 



rest; and philosophic bota- 



nists are agreed that the tree is a colony of individ- 



ual plants not one plant. 



Let us pass from the coral to the stem of some 

 other polype, say a Campanularia. Above is the 

 representation of such a stem, of the natural size, 

 and beside it a tiny twig much magnified. You 

 observe the ordinary polype issuing from one of the 

 capsules, and expanding its coronal of tentacles in 

 the water. The food it secures will pass along the 

 digestive tract to each of the other capsules. Un- 

 der the microscope you may watch this oscillation 



(mag . 



