POLYPES. 169 



atmospheric influence, while others avoid it. The 

 marine ones frequently plant themselves on rocks, 

 in different aspects, often regulated by the cli- 

 mate. They rarely expose themselves to violent 

 currents, or the direct shock of the waves. They 

 are often found in the hollows of rocks or sub- 

 marine grottoes, and in gulfs where the water is 

 less agitated. 



It was observed above that the Infusories pre- 

 sent some analogy to the seeds of vegetables ; 

 the polypes go further, and represent, often most 

 exactly, the developed plant from the tree, by 

 almost all the intermediate stages, to the fungus, 1 

 at least the fixed polypes: these appear, as it 

 were, to take root, to send forth branches which 

 produce seeming blossoms, composed of what 

 appear to be petals arising from a calyx, 

 arranged sometimes in a single and at others 

 in a double circle, and in some including the 

 semblance of stamina ; they are also very 

 sensible to the light, and turn to its source, and 

 like plants are readily propagated by cuttings 

 and buds ; so that all the older naturalists re- 

 garded them as real plants, without apparently 

 suspecting their animal nature. Ancient natu- 

 ralists were very apt to mistake analogical 

 resemblances for proofs of affinity, but in the 

 progress of science, when natural objects were 



1 PLATE II. 



VOL. I. M 5 



