G O R G O N I A. 79 



The laft thing which I thai 1 offer againft their growing 

 like vegetables, is the fituation and growth of the me- 

 dulla, which is obferved in fome particular fpecies of thefe 

 animals. This, had it been fimilar to the pith in the 

 young branches of trees, would have been a very ftrong 

 argument in favour of their partaking of a vegetable na- 

 ture : but the cafe is otherwise. For inftance, let a young 

 branch of a Gorgonia ceratophyta be diffecled longitudi- 

 nally, fo as to (hew the courfe of the medulla in the lead- 

 ing branch, as well as the fide branches, tab. 9. fig. 5. 

 6. Divide, at the fame time, and in the fame manner, 

 a young fprig of any common tree, a lime-tree, for in- 

 ftance, fig. 7. 8. In the lime-tree we mall obferve a free 

 communication of the pith between the leading branch 

 and the fide branches ; but in the Gorgonia the pith or 

 medulla of the leading branch has no communication in 

 the leaft with the fide branches. The primary branch 

 being furrounded with a horny tube to the extremity, and 

 when it is longitudinally diffected, we plainly difcover 

 the feptum, that is, the continued fide of the tube, which 

 prevents any communication. The branches here arife 

 on the fide of the leading branch, each forming or pro- 

 ducing a medulla proper to itfelf, without any communi- 

 cation with the medulla of the primary branch. It is ex- 

 actly the fame in the genus of Antipathes. The medulla 

 in thefe fpecies of Gorgonias confifts of certain white 

 membranes, placed at diftances nearly equal to their dia- 

 meter, croffing the little tube that contains them, like fo 

 many diaphragms ; whereas the medulla of young 

 branches of trees confifts of fpongy fhining globules,, 

 clofely compacted together, 



1 . Gorgonia 



