FLORIDA REEFS. 59 



which time we have no evidence of any change in species, but, on the 

 contrary, the strongest proof of the absolute permanence of those species 

 whose past history we have been able to trace. 



Before leaving the subject of the coral reefs, I would add a few words on 

 the succession of the different kinds of Polyp corals on a reef as compared 

 with their structural rank and also with their succession in time, because we 

 have here another of these correspondences of thought, those intellectual 

 links in creation, which give such coherence and consistency to the whole 

 and make it intelligible to man. 



The lowest in structure among the Polyps are not corals, but the single, soft- 

 bodied Actiniae. They have no solid parts, and are independent in their 

 mode of existence, never forming communities, like the higher members of 

 the class. It might at first seem strange that independence, considered a 

 sign of superiority in the higher animals, should here be looked upon as a 

 mark of inferiority. But independence may mean either simple isolation, or 

 independence of action ; and the life of a single Polyp is no more indepen- 

 dent in the sense of action than that of a community of Polyps. It is sim- 

 ply not connected with or related to the life of any others. The mode of 

 development of these animals tells us something of the relative inferiority 

 and superiority of the single ones and of those that grow in communities. 

 When the little Polyp coral — the Astraean or Madrepore, for instance — is born 

 from the egg, it is as free as the Actinia, which remains free all its life. It is 

 only at a later period, as its development goes on, that it becomes solidly 

 attached to the ground, and begins its compound life by putting forth new 

 beings like itself as buds from its side. Since we cannot suppose that the 

 normal development of any being can have a retrograde action, we are justi- 

 fied in believing that the loss of freedom is in fact a stage of progress in 

 these lower animals, and their more intimate dependence on each other a 

 sign of maturity. 



There are, however, structural features by which the relative superiority 

 of these animals may be determined. In proportion as the number of their 

 parts is limited and permanent, their structure is more complicated ; and the 

 indefinite multiplication of identical parts is connected with inferiority of 

 structure. Now in these lowest Polyps, the Actinise, the tentacles increase 

 with age indefinitely, never ceasing to grow while life lasts, new chambers 

 being constantly added to correspond with them, till it becomes impossible to 

 count their numbers. Next to these come the true Fungidae. They are also 



