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called the florets, seems formed without sufficient room or 
opening for it to protrude: but we presume that, although a 
Coralline, it may have the power of opening the larger 
segment when fresh, which a coriaceous suhstance natu- 
rally admits of; so that the larger valve is a kind of door, 
and is a strong characteristic of the species, although it is 
sometimes much obliterated. We are not sure that this 
has been figured at all, as the segment which is so re- 
markable does not appear to have been noticed. It may be 
worthy of observation here, that in some instances the 
coriaceous substance which covers the darker branches all 
round, and protrudes, as at the right hand figure, often 
appears quite distinct from it, and Naturalists have called 
this blacker substance by the name of Isis. It may per- 
haps be the work of a separate animal, associated, as in 
these instances, with the Gorgonia. 
