SEA-MATS AND SHELLY COEALLIHES. Y7 



other animal caught by the bird's head of a Polyzoan, 

 and tightly held, would presently die ; and though in 

 its own substance it would not yield any nutriment to 

 the capturer, yet by becoming the centre of a crowd of 

 busy infusoria, multitudes of which would constantly be 

 drawn into the tentacular vortex, and swallowed, it 

 would be ancillary to its siipport, and the organ in 

 qiiestidn would play no unimportant part in the econ- 

 omy of the animal. 



