226 SEA-SIDE STUDIES. 



should we, otherwise than in easy speech, talk of the 

 Digestion of a Polype, meaning thereby its Nutri- 

 tion. The 2^u7yose of a leg, jDrogression, is fulfilled 

 by the cilia, which move the animalcule ; the purpose 

 of Digestion, preparation of food, is performed by the 

 cavity of the Polype ; but the specific organs named 

 legs and alimentary canal, and the specific functions 

 of those organs (Walking and Digestion), are in both 

 cases absent. 



If the reader has followed me thus far, he will 

 have understood that, when I doubted whether the Ac- 

 tiniae digested, there was no doubt entertained of their 

 power of preparing food, but only of their power of 

 chemically digesting it. I doubted, in short, whether 

 they should not be separated from the more complex 

 animals which digest, and whether they should not 

 rank in M. Bernard's second class. "VVe do not call a 

 hut or group of cottages a city. We do not speak 

 of its commerce, its government, its literature ; these 

 are social functions developed in a complex city, not 

 possible in a group of cottages. In the same way we 

 should not expect to find Digestion, Respiration, or 

 any other complex function, in animals so simple as 

 a Sea -Anemone. Nor could the notion ever have 

 gained currency, had there been the proper jDrecision 

 in our zoological language, and had not the "fallacy 

 of observation'' misled us. 



Now to the experiments. The first point to be 

 settled was this : Have the Polypes anything of the 



